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Scientific Data Documentation
Public Use Microdata Sample, 1980

cc36.census.pums80.zip

Notes
Abstract
Summary Data
Public Use Microdata
Proccessing the Data
Accuracy of the Microdata Sample Estimates
Sample Design for the Public Use Microdata Samples
Record Contents

NOTES

  1. Data for each state are stored in separate files inside the zip file, 
     named by state abbreviation.

  2. Data are in simple text files (ASCII) in fixed format layout.

ABSTRACT

 Overview

 Public-use microdata samples are computer tapes which contain records for a
 sample of housing units, with information on the characteristics of each unit
 and the people in it.  In order to protect the confidentiality of
 respondents, the Bureau excludes identifying information from the records.
 Within the limits of the sample size and geographic detail provided, these
 tapes permit users with special needs to prepare virtually any tabulations of
 the data they may desire.

 Three separate public-use microdata samples are available, each representing
 five percent or one percent of the population and housing of the United
 States:

        A Sample, 5%, identifying all States and various subdivisions within
        them, including most counties with 100,000 or more inhabitants;

        B Sample, 1%, identifying all metropolitan territory and most SMSAs
        individually, and groups of counties elsewhere;


        C Sample, 1%, identifying regions, divisions, and most States by type
        of area (urban/rural).

 Three 1-in-1,000 samples are also prepared, one each extracted from the A, B,
 and samples.

 Comparison Of Summary Data and Microdata

 Figure 1 illustrates the basic distinctions between summary data and
 microdata.  Summary data are the type of data found in census printed
 reports, summary tape files, microfiche, and most special tabulations.  In
 summary data, the basic unit of analysis is a specific geographic area (for
 example, a census tract, county, or State) for which counts of persons or
 housing units in particular categories are provided.  In microdata, the basic
 unit is an individual housing unit and the persons who live in it.

 There are two types of microdata:  confidential microdata and public-use
 microdata.  Confidential microdata include the census basic record tapes,
 computerized versions of the questionnaires collected from households, as
 coded and edited during census processing.  The Census Bureau tabulates these
 confidential microdata in order to produce the summary data that go into the
 various reports, summary tape files (STFs), and special tabulations.  Public
 -use microdata samples are extracts from the confidential microdata taken in
 a manner that avoids disclosure of information about identifiable households
 or individuals.

 Figure 1.  Comparison of Summary Data With Information on Microdata Files
SUMMARY DATA

        Basic unit is an identified geographic area
        Data summarized on people with housing in areas
        Available for small areas

  Illustrative Summary Data

                        Occupied  Number of   Renter        Gross Rent
                Total    Housing   Persons   Occupied   Under  $80-   $100-
     City        Pop.     Units   Per Unit     Units     $80    99     149

 Weston City   110,938    49,426     2.2      31,447     858   3,967  13,282
 Smithville     21,970     7,261     3.1       2,492      37     190   1,766
 Junction       17,152     5,494     2.7         822      11      29     238

PUBLIC USE MICRODATA

        Basic unit is an unidentified housing unit and its occupants
        Unaggregated data to be summarized by the user
        Allows detailed study of relationships among characteristics
        Not available for small areas

 Illustrative Microdata

                  State of    Metro/     Persons in
                  Residence   nonmetro   household   Telephone   Plumbing

 Housing Unit #1  Virginia    Metro          3           Yes        Yes

                  Rent        Automobiles     Household
                                              type

                  $325             2          Married-couple family     F

                                        Place   Years
                                        of       of
           Relationship Sex  Age  Race  Birth   School Occupation Earnings

 Person a  Householder   M    37    W   Kansas    12   Plumber     $22,100   B
 Person b  Spouse        F    35    W   Virginia  12
 Person c  Child         M     6    W   Virginia   1

                  State of    Metro/     Persons in
                  Residence   nonmetro   household   Telephone   Plumbing

 Housing Unit #2  Virginia    Nonmetro       1           Yes        Yes

                                              Household
                  Rent        Automobiles     type

                  $150             1          Nonfamily householder

                                       Place   Years
                                       of       of
           Relationship Sex  Age  Race Birth   School Occupation  Earnings

 Person a  Householder   F    62    B  Alabama   16   Elementary  $15,300   1d
                                                        teacher

                  State of    Metro/     Persons in
                  Residence   nonmetro   household   Telephone   Plumbing

 Housing Unit #3  Virginia    Metro          0           N/A        Yes

                  Rent        Automobiles     Household
                                              type

                  $205            N/A         Vacant

 *Public-use microdata samples do not actually contain alphabetic information.
 Such information is converted to numeric codes; for example, the State of
 Virginia has a numeric code of 51.

 Protecting Confidential Information

 Records on public-use microdata samples contain no names or addresses.  Also,
 the Bureau limits the detail on place of residence, place of work, high
 incomes, and selected other items to further protect the confidentiality of
 the records.  Microdata records identify no geographic area with fewer than
 100,000 inhabitants.  Microdata samples include only a small fraction of the
 population, drastically limiting the chance that the record of a given
 individual is even contained in a microdata file, much less identifiable.

 Uses of Microdata Files

 Public-use microdata files essentially make possible "do-it-yourself" special
 tabulations.  The 1980 files furnish nearly all of the detail recorded on
 long-form questionnaires in the census.  Subject to the limitations on sample
 size and geographic identification, it is possible for the user to construct
 a seemingly infinite variety of tabulations interrelating any desired set of
 variables.  Users have the same freedom to manipulate the data that they
 would have if they had collected the data in their own sample survey, yet
 these files offer the precision of census data collection techniques and
 sample sizes larger than would be feasible in most independent sample
 surveys.

 Microdata samples will be useful to users (1) who are doing research that
 does not require the identification of specific small geographic areas or
 detailed cross tabulations for small populations, and (2) who have access to
 programming and computer time needed to process the samples.  Microdata users
 frequently study relationships among census variables not shown in existing
 census tabulations, or concentrate on the characteristics of certain
 specially defined populations, such as unemployed homeowners or families with
 four or more children.

 Sample Design and Size

 Each microdata file is a stratified sample of the population, actually a sub-
 sample of the full census sample (19.4% of all households) that received
 census long-form questionnaires.  Sampling was done household-by-household in
 order to allow study of family relationships and housing unit
 characteristics.  Sampling of persons in institutions and other group
 quarters was done on a person-by-person basis.  Vacant units were also
 sampled.

 There are three independently drawn samples, designated "A," "B," and "C,"
 each featuring a different geographic scheme, as discussed below.  The B and
 C Samples each contain 1 percent, i.e., one household for every one hundred
 households in the Nation.  Samples from the 1970 and 1960 censuses also
 employed a 1-percent sample size.  New for 1980 is a 5-percent sample,
 designated the A Sample, which includes over one-fourth of the households
 that received the census long-form questionnaire.  Nationwide, the A Sample
 gives the user records for over 11 million persons and over 4 million housing
 units.  (One could even use the A, B, and C Samples together, if there were
 an advantage in having a 7-percent sample, since there is negligible overlap
 among the samples).  On the other hand, since processing a smaller sample is
 less expensive, some users will be interested in one of the one-in-a-thousand
 samples (extracts of the 1-percent and 5-percent samples) which are also
 available from the Census Bureau.  Sample design is discussed more thoroughly
 in chapter 4.

 The samples are self-weighting.  The user can estimate the frequency of a
 particular characteristic for the entire population by tallying records from
 the microdata files and multiplying the result by the inverse of the sampling
 rate, e.g., multiplying raw counts from the 5-percent A Sample by 20.  A
 section of chapter 2 discusses the preparation and verification of estimates
 (see page 14).

 Reliability improves with increases in sample size, so the choice of sample
 size must represent a balance between the level of precision desired and the
 resources available for working with microdata files.  By using tables
 provided in chapter 3 (see page 20), one can estimate the degree to which
 sampling error will affect any specific number prepared from a microdata file
 of a particular sample size.  (It is also possible to estimate sampling error
 using 100 "random groups" identified on sample records, see page 27).  Users
 of microdata files for State or SMSA estimates would normally use a 1- or 5-
 percent sample, while users concerned only with national figures can
 frequently get by with a 0.1 percent (one-in-a-thousand) sample.  Even
 national users may need a 1-percent or 5-percent sample if they contemplate
 extremely detailed tabulations or are concerned with very small segments of
 the population, for example, males 65 years old or over of Italian ancestry.
 one of the examples in chapter 3 discusses the selection of appropriate
 sample size for a particular study.

 Subject Content

 With only minor exceptions, microdata files contain the full range of
 population and housing information collected in the 1980 census:  503
 occupation categories, age by single years up to 90, income by $10 intervals
 up to $75,000, and so forth.  Because the samples provide data for all
 persons living in a sampled household, users can study how characteristics of
 household members are interrelated (for example, income and educational
 attainment of husbands and wives).

 Information for each housing unit in the sample appears on a 193-character
 record with geographic and housing items, followed by a variable number of
 193-character records with person information, one record for each member of
 the household.  Items on the housing record are listed beginning on page 52;
 items on the population record are listed beginning on page 53.  Each of the
 items is further defined in the glossary (reprinted from the 1980 Census
 Users' Guide), presented as Appendix K to this document.

 Data users will frequently want to generate additional variables or otherwise
 recode these items.  For instance, a user desiring data on years of school
 completed must construct this variable from the item included on highest
 grade attended--reducing that value by one year for all persons who had not
 finished that grade, as shown in another item on the record.  Transformations
 such as this, as well as corrections that apply to certain subjects, are
 discussed in Appendix J.

 There are no "missing data" categories in most items on these files.
 Substitutions or allocations have been made for any missing data resulting
 from incomplete questionnaires, inconsistent information or equipment
 malfunction.  "Allocation flags" appear at the end of each record indicating
 each item which has been allocated.  Thus, a user desiring to tabulate only
 actually observed values can eliminate those cases with allocated values.
 Allocation flags are discussed further on page 33.

 Geographic Identification

 The A, B, and C Samples each feature a different geographic scheme:

        The A Sample, 5-percent size, identifies every State and most
        individual counties with 100,000 or more inhabitants (350 in all, see
        Appendix B.2).  In many cases individual cities (see Appendix B.3) or
        groups of places with 100,000 or more inhabitants are also identified.

        Counties with populations under 100,000 have been grouped into vision
        statement analytic units proposed by State Data Centers.  These
        frequently follow SMSA or State planning district boundaries.  (Those
        SMSA's shown on the A Sample are listed in Appendix B.1.)  In New
        England, areas are defined in terms of cities and towns rather than
        counties.

        The term "county group" is used loosely to apply to each of the areas
        identified on these files.  A 3-digit number, unique within State,
        identifies each area.

        The B Sample identifies 282 SMSAs of 100,000 or more inhabitants.  The
        remaining 36 SMSAs are paired together so that metropolitan and non-
        metropolitan territory can be separately analyzed.  (SMSAs not shown
        separately are footnoted in Appendix B.1.)  Thirty-one States are not
        separately identified because they contain SMSAs which cross State
        boundaries and have fewer than 100,000 persons within a State (See
        Appendix C).  Many large cities, groups of cites, and counties are
        identified within large SMSAs.  (See Appendixes B.2 and B.3.)  Outside
        SMSAs, counties are grouped according to State planning district or
        into other reasonable analytic units with populations of 100,000 or
        more.

        The C Sample identifies 27 States and the District of Columbia.  The
        remaining States are shown in eight groups, none of which crosses a
        census region or division boundary (see Appendix A).  Four type-of-
        area categories are shown throughout:  central cities of urbanized
        areas, urban fringe (i.e., the remainder of urbanized areas outside
        central cities), other urban, and rural.  Seventy-three individual
        urbanized areas are shown (see Appendix D), all of which have at least
        100,000 inhabitants in the central city and another 100,000 in the
        urban fringe.  This happens to include every urbanized area with a
        total population over 800,000, and roughly half of the urbanized areas
        between 200,000 and 800,000.

 The characteristics of the three different geographic schemes are compared in
 figure 2.

 Figure 2.  Comparison of Features on 1980 and 1970 Public-Use Microdata
            Samples
                        -----1980 Samples-----      -------1970 Samples-------
                                                               County   Neigh.
                           A       B       C         State     Group    Chars.

 Sample Size                5%      1%      1%        1-2%      1-2%      1-2%
                          0.1%    0.1%    0.1%        0.1%      0.1%      0.1%

 Areas Identified

   Divisions                X       -       X           X        -         X
   States                   51      20      28          51        4        -
   SMSAs of 100,000+       180     282      -           -       125        -
   Counties of 100,000+    350     236      -           -       104
   Places of 100,000+      123     135      58          -        12        5
   County Groups          1154    1258      -           -       409
   Urbanized Areas          -       -       73          -        -         6
   Metro/Nonmetro           -       X       -        23 States   -         -
   Urban/Rural              -       -       X        42 States   -         X

 Neighborhood
   Characteristics          -       -       -           -        -         X

 Maps of county groups shown on the A and B Samples are included as appendixes
 L and N, respectively.  Where county group boundaries subdivide a county, as
 in the identification of a city, lists of subcounty units in appendixes M and
 O supplement the maps.  The maps are also available as single nationwide
 sheets, 30" x 42", with county group boundaries shown in color.
 Comprehensive listings of county group components, illustrated in figure 3,
 are available on microfiche.  The components of each county group are also
 derivable from a computerized County Group Equivalency File available
 separately.

 The 1-in-1,000 samples (0.1%) extracted from the A, B, and C Samples have the
 same geography as the parent files.

 Migration and Place-of-Work Data

 The A and B Sample county groups apply not only to 1980 residence, but also
 to place of work in 1980 and to place of residence in 1975.  This makes
 possible the detailed analysis of migration and commuting patterns in terms
 of origin and destination.  For instance, one can examine immigrants to an
 area (i.e., people who lived in a different area in 1975) in terms of the
 States or metropolitan areas from which they came.  Further, if one purchases
 data for the entire U.S., one can also examine the characteristics of
 outmigrants (i.e., persons who lived in a particular county group in 1975 who
 resided elsewhere in 1980).  Similarly, one can look at the characteristics
 of the work force in an area using the county group of work, irrespective of
 whether workers reside in the same area.

 Migration, place of work, and travel time to work appear on these files only
 for one-half of the sampled households.  (Due to budgetary limitations, only
 part of the questionnaires could be coded.)  Thus, the 5-percent sample
 includes only a 2 1/2-percent sample for migration and place of work.
 Therefore, the user must double the normal weights to derive estimates, as
 discussed further in chapter 2.
 
 Corresponding Microdata From Earlier Censuses

 The Census Bureau created six separate 1-percent (one-in-a-hundred) samples
 from the 1970 census, three based on the 15-percent versions of the 1970
 questionnaire, and three based on the 5-percent version.  Geographic areas
 identified on 1970 and earlier microdata files were required to have at least
 250,000 inhabitants.  One geographic scheme employed in 1970 identified
 States, a second identified SMSAs with 250,000 or more inhabitants and
 similarly large county groups elsewhere, and the third identified only very
 large areas but included records for "neighborhood characteristics."  A
 single one-in-a-hundred sample, identifying States, is available from the
 1960 census.  Characteristics of these 1970 geographic schemes are summarized
 in figure 2.

 The files from 1960 and 1970 use basically similar formats.  The 1980
 microdata record layouts differ from their 1960 and 1970 counterparts; but,
 since most of the 1980 items were also included in the 1970 and 1960
 censuses, these microdata files represent a rich resource for analysis of
 trends.  Items which were added, dropped, or substantially changed between
 1970 and 1980 are listed in figure 4.  The glossary, presented as Appendix K
 to this document, discusses historical comparability of 1980 data items in
 greater detail.

 Geographic comparability is a larger problem.  States can be identified on
 microdata from each census (the 1960 and 1970 State samples and the 1980 A
 Sample).  Regions and divisions by type-of-area are derivable from the 1980 C
 Sample and the 1970 "neighborhood characteristics" samples.  Many, but far
 from all, counties of 250,000 or more population in 1970 are identified on
 the 1970 "County Group" Samples.  These large counties typically are also
 shown on the 1980 A Sample (and frequently also the B Sample).  Counties
 identified in both 1980 and 1970 are asterisked in Appendix B.2.

 SMSAs are not always directly comparable between 1970 and 1980, however,
 since roughly half of the SMSAs identified in 1970 files changed boundaries
 prior to the 1980 census.  In other words, a 1970 SMSA identified as a county
 group may not match the corresponding 1980 SMSA shown on the B Sample.  No
 individual place or place group was shown prior to 1980.  Outside identified
 SMSAs there is almost no commonality between 1970 and 1980 county groups.
 1970 county groups were based on "functional economic areas" defined by the
 Bureau of Economic Analysis.  These frequently crossed State lines and
 involved grouping criteria unrelated to the administrative and local interest
 factors that contributed to the definition of county groups in 1980.

 Figure 4.  1970-1980 Subject Comparability

 1980 Items Not on 1970 Files:

 Ancestry
 Boarded-up vacant unit
 Carpooling
 Condominium
 Language spoken at home and ability to speak English
 Hours usually worked per week last year
 Public transportation disability
 Selected monthly owner costs
 Travel time to work (shown only for half of the samples)
 Vans or light trucks available
 Weeks unemployed last year

 Concepts Substantially Changed:

 Farm definition - old definition can be reconstructed
 "Householder" places household head concept
 Industry - many code changes; classification system changed somewhat
 Occupation - classification system and codes substantially changed
 Poverty definition - minor modifications; the old definition could be
      reconstructed if necessary
 Race - several categories added; revised classification rules affect White
      and Other
 Residence in 1975/Place of work - broad categories in 1970, but coded to
      county group in 1980 on the A and B Samples; (shown only for half of the
      sample)
 Telephone in unit - narrower than telephone availability in 1970
 Work disability - not counted for 1980 if it has lasted less than six months

 1970 Items Not On 1980 Files:

 Basement
 Battery radio
 Birthplace of parents (allowing identification of "foreign stock")
 Clothes dryer
 Clothes washing machine
 Dishwasher
 Duration of disability
 Home food freezer
 Industry and occupation 5 years ago
 Mother tongue
 Owner-occupied cooperative/condominium
 Second home
 Television
 Vocational training
 Year moved into unit (retained for householders, deleted for other persons)

 Further information on the 1970 microdata files is contained in Public-Use
 Samples of Basic Records From the 1970 Census:  Description and Technical
 Documentation and its three supplements, available for $5 from Customer
 Services.  A map, 22 by 32 inches, defining areas identified on the 1970
 County Group Samples is included with the documentation.  Documentation for
 the 1960 microdata file is also available for $5.

 Public-use microdata samples are being created from manuscript records of the
 1940 and 1950 censuses, and will probably be available in late 1983.
PROCESSING THE DATA

 Technical Conventions

 A printout included with each tape copy purchased from the Census Bureau
 includes the following information, some of which document options selected
 by the purchaser:

                 Recording Language (ASCII or EBCDIC)
                 Density (1600 bpi or 6250 bpi)
                 Labelling (Label or no label)
                 Block Length (Any multiple of 193, up to 32617)
                 Record Length (193)
                 Record Count

 Units of Issue

 A total of 142 files are available in the A, B, and C Samples:

        A Sample = 5 percent:  51 files

                 One file for each State and the District of Columbia

              0.1 percent:  1 nationwide file

        B Sample = 1 percent:  52 files

                 One file for each State and the District of Columbia,
                   exclusive of all county groups crossing State lines

                 One file for all county groups in the nation crossing State
                   lines (listed in Appendix C)

              0.1 percent:  1 nationwide file

        C Sample = 1 percent:  36 files

                 One file for each of the 27 States separately identified
                   and 1 for the District of Columbia

                 One file for each of the 8 groups of the remaining States
                   specified in Appendix A.

              0.1 percent:  1 nationwide file

 Each of these files may be purchased separately.  Single file tapes are
 priced at $140 per reel (as of January 1, 1983).  Most files are sufficiently
 small so that more than one can be accommodated on a single reel.  Tapes with
 more than one file copied onto them are priced at $165 per reel.  Purchasers
 of the B Sample for any of the 31 States which include area in a county group
 crossing State lines may want to request that the "State Code 99" file be
 stacked onto a tape being purchased.  Estimates of the number of tapes
 required for specified groups of files at a given density and blocking factor
 are available on request from Customer Services.
 
 File Structure

 Each file consists of a series of 193-character logical records of two types
 --housing and persons.  Each housing unit record is followed by a variable
 number of person records, one for each member of the household or none if
 vacant, as illustrated in figure 1 on page 2.  Each person in group quarters
 has two records--a dummy "housing unit" record (most nongeographic fields are
 not applicable), as well as a person record.

 In the text of this document, the numeric identification of a particular data
 item is the same as its character location within a record.  Items on the
 housing record are prefixed with an H, population items with a P.  For
 instance, Race, item P12-13, is a two-digit code beginning in character 12 of
 the person record.  (The data dictionary, or record layout, also introduces
 mnemonic identifiers; see p. 54.)

 Geographic identifiers, subsample identification and serial numbers appear
 only on the housing unit record.  Thus, most tabulations of person
 characteristics require manipulation of both housing and person records.  An
 item on the housing record indicates the exact number of person records
 following before the next housing record (H26-27).  This feature allows a
 program to anticipate what type of record will appear next, if necessary.

 In order to use many software packages (e.g., BMD), users need to create
 rectangular files , i.e., extract files with any desired household data
 repeated with each person's record.  While this imposes an intermediate
 processing step on the user of such software, it will benefit those users who
 are able to reduce significantly the size of the file.  The Census Bureau's
 CENSPAC system can be used to generate rectangular extract files.

 Alternatively, users may obtain a software package capable of handling the
 hierarchical structure or prepare their own software.  The Census Bureau
 offers such a software package called COCENTS, and others are available from
 commercial sources (for example, SAS).  Descriptions of CENSPAC and COCENTS
 are available upon request from Customer Services.

 All fields are numeric, except for the Record Type which uses "H" and "P."

 File Size

 A printout included with each tape copy purchased from the Census Bureau
 includes the total record count.  A future supplement to this document will
 contain record counts for each area identified.  In the absence of those
 counts, the number of 193-character records can be estimated as follows:  Sum
 the total number of persons, the total number of housing units and the number
 of persons in group quarters (for whom there is a dummy housing unit record);
 multiply that sum by the sampling rate.  For example; the number of records
 on the 5-percent A Sample nationwide can be estimated as 226,545,805
 (persons) + 88,411,263 (housing units) + 5,714,931 (persons in group
 quarters) = 320,671,999; x .05 = 16,033,600.

 Record Sequence

 Records on these files are sorted by geographic area.  On the A and B
 Samples, all households sampled within a particular county group appear
 together.  County groups are sequenced in ascending order within State.  On
 the 0.1% nationwide files, States are sequenced by State code.  On the B
 Sample, this means that all county groups with State code suppressed (i.e.,
 shown as 99) appear at the end of the nationwide file.

 On the C Sample, records are sequenced by urbanized area code by type of area
 code within State or State group.  Thus, households outside an identified
 urbanized area (i.e., UA code 0000) appear first, further grouped by type-of-
 area code, followed by data for each identified UA in ascending code
 sequence, central city households preceding urban fringe households.  On the
 0.1% sample, States and State groups appear in code sequence.

 The sequence of households within each identified geographic area has been
 scrambled to avoid any implication of geographic information beyond that
 which meets Census Bureau disclosure rules for public-use microdata.

 Person records within household are sequenced by relationship code (P2).
 Thus, for example; the record for the householder always immediately follows
 the housing unit record for an occupied unit.  This feature simplifies
 tabulation of households or families by race of householder, ancestry of
 householder, and even poverty status--characteristics not included on the
 housing unit record--since the desired indicators are always on the first
 person record.  Where the household contains more than one person of a given
 relationship, person records appear in sequence of decreasing age (P8-9).

 Persons sampled from within the same group quarters are not identifiable as
 such, since each has an independent dummy housing unit record.

 Machine-Readable Documentation

 The "data dictionary" or record layout which appears on pages 55 to 99 was
 generated from a machine-readable file which is sold as part of the CENSPAC
 system ($140) or may be obtained in conjunction with the County Group
 Equivalency File (see below).  Using that file it is possible to
 automatically generate hard copy documentation for extract files or labels
 for tabulations created with CENSPAC.  With some adaptation, the data
 dictionary file can also be used by other software packages or user programs
 to automatically specify the layout of the microdata files.

 Also available in machine-readable form is the County Group Equivalency File
 ($140), a list of counties (and places or MCDs where applicable) and their
 assigned county group codes for the A and B samples.  The printout in figure
 3 was generated from a resorted version of this file.

 Handling Invalid Codes

 The data dictionary shows each category as having a unique representation.
 It is possible, however, that certain variables may have a small number of
 cases outside the intended range.  Standard census practice is to assign
 invalid codes to the next lower numbered valid category.  For example, on an
 allocation flag with valid codes 0, 2 and 3, a 1 would be counted with code
 0, and a code of 4 or more would be counted with 3.  Exceptions to this rule
 occur in occupation and industry codes, where invalid codes are assigned to
 the next higher valid category.

 Preparing and Verifying Tabulations

 Estimation of totals - Estimates of complete-count census figures may be made
 from tabulations of public-use microdata samples by using a simple inflation
 estimate - that is, by multiplying the sample tally by the reciprocal of the
 sampling rate.  For example, to estimate the total number of persons with a
 certain population characteristic from a one-in-one-hundred sample, multiply
 the sample total by 100; from a 5-percent sample, multiply by 20.  To
 estimate the number of persons who lived in a different county in 1975, data
 for which only one-half of the sample is available, multiply an A Sample
 table by 40 (i.e., the reciprocal of 1/2 of 5-percent).  Persons in the
 migration/place work/travel time sample carry a weight of 2 in character P46;
 all others carry a weight of 0.

 Estimation of percentages - Percentages are estimated by simply dividing the
 weighted estimate of persons or housing units with a given characteristic by
 the weighted sample estimate for the base.  Normally, this yields the same as
 would be obtained if one made the computation using sample tallies rather
 than weighted estimates.  For example, the percentage of housing units with
 air conditioning in a one-in-one-hundred sample can be obtained by simply
 dividing the tally of sample housing units with air conditioning by the total
 number of sample housing units.  When working with migration, place of work
 or travel time to work figures, one must either take care to determine both
 the numerator and base of the percentage from the 1/2 sample, or must use
 weighted estimates in calculations rather than simply tallies.

 Verifying tabulations   - The 1980 public-use microdata samples have been
 constructed so that it should not be difficult to obtain desired tabulations.

 File structure and coding of items is straightforward.  There are no missing
 data (see the section on allocations, page 33).  Records not applicable for
 each item are assigned to specific "NA" categories, and it is frequently not
 necessary to determine in a separate operation whether a record is in the
 universe or not.  A user must, however, anticipate the possibility of errors
 in his or her own processing.  Thus, user tabulations should be verified
 against other available tallies.  Two ways for the user to verify estimates
 follow:

 1.  Using control tabulations from the samples

     As each public-use microdata sample was produced, counts of persons,
     housing units, vacant housing units, and group quarters persons
     selected into the sample were tallied within each identified geographic
     area.  These control counts will be published as a supplement to this
     documentation.  (In the interim, counts for specific areas may be
     requested from Customer Services.)  A failure of user tallies to
     replicate these exact counts would indicate an error in the user's data
     processing.

 2.  Using published data from the 1980 census

     Tabulations from the 1980 census data base are available in the printed
     census publications and on summary tape files.  The tabulations provide
     an opportunity to check the reasonableness of statistics derived from
     public-use microdata samples.  A familiarity with summary data already
     available may also facilitate planning of tabulations to be made from
     microdata.  Those publication series likely to be of greatest use for
     this purpose are listed in figure 5.

     In comparing sample tabulations with published data one must carefully
     note the universe of the published tabulation.  For instance, on
     microdata records, Industry (P87-89) is reported for the civilian labor
     force and for persons not in the labor force who reported having worked
     1975 or later.  Industry tabulations in 1980 census publications are
     presented only for the employed population or the experienced civilian
     labor force.  Thus, a tally of industry for all persons for whom industry
     is reported on microdata records would not correspond directly to any
     published tabulation.  A user should always pay particular attention to
     concept definitions as presented in the glossary.

     One cannot, of course, expect exact agreement between census publications
     (which are based on the complete census count, full sample estimates, or
     a subsample of the census sample) and user estimates based on tallies of
     a 5-percent of smaller sample.  They will inevitably differ to some
     extent due to chance in selection of actual cases for public-use
     microdata samples.  Since the amount of likely chance variation for a
     given statistic can be measured, any discrepancy beyond a certain level
     can be identified as a likely error in programming.  Chapter 3 discusses
     sampling variability and its measurement.

     User experience has indicated that careful verification of sample
     tabulations is essential -- so important that it may frequently be
     advisable to include additional cells in a tabulation for no other reason
     than to provide counts or to yield marginal totals not otherwise
     available, which may be verified against other available tabulations.

 Figure 5.  Selected 1980 Census Publications Useful in Verifying
            Microdata Tabulations

 PHC80-52   Advance Estimates of Social Economic and Housing
              Characteristics

              Basic distributions for most census items, for States,
              counties, places of 25,000 or more inhabitants; issued
              by State.

 PC80-1-B   General Population Characteristics

 HC80-1-A   General Housing Characteristics

 PC80-1-C   General Social and Economic Characteristics             (mid 1983)

 HC80-1-B   Detailed Housing Characteristics                        (mid 1983)

              Distributions in somewhat greater detail than PHC80-52,
              many also shown for race and Spanish origin groups
              (PC80-1-C also features characteristics for ancestry
              groups); for States, SMSAs, urbanized areas, counties,
              places of 2,500 or more inhabitants.  Characteristics
              by type of area (as in C Sample) are also shown at
              the State level.  All issued by State.

 PC80-1-D   Detailed Population Characteristics                    (late 1983)

 HC80-2     Metropolitan Housing Characteristics                   (late 1983)

              Crosstabulations of characteristics, some in
              considerable detail.

                PC80-1-D reports, issued by State, show the State
                and SMSAs with 250,000 or more inhabitants.  The
                HC80-2 series includes a report for each SMSA
                regardless of size, as well as a report for each
                State.

 PC80-2     Population Subject Reports                             (1983-1984)

 HC80-3     Housing Subject Reports                                (1983-1984)

              Very detailed cross tabulations, most shown only at
              the national level.  A series of nationwide reports
              issued by Subject.


 These publications are available for sale through the Superintendent of
 Documents, Government Printing Office, Washington, D.C.  20402.
ACCURACY OF THE MICRODATA SAMPLE ESTIMATES

 Introduction

 The data summarized from a public-use microdata sample not only describe the
 particular set of households in the sample, but are primarily used to
 estimate what data would have been obtained if a complete census count of the
 variables of interest were available.  These estimates can be expected to
 vary from the complete-count result, because they are subject to two basic
 types of error --- sampling and nonsampling.  The sampling error in the data
 arises from the selection of persons and housing units to be included in both
 the census sample and the microdata samples.  The nonsampling error, which
 affects both sample and complete count data, is the result of all other
 errors that may occur during the collection and processing phases of the
 census.  A more detailed discussion of both sampling and nonsampling error is
 given in this chapter.  Chapter 4 describes the method used to select the
 microdata samples.

 Errors in the Data

 Since the estimates that users produce are based on a sample, the data may
 differ somewhat from complete-count figures that would have been obtained if
 all housing units, persons within those housing units, and persons living in
 group quarters had been enumerated using the same questionnaires,
 instructions, enumerators, etc.  In addition, if one were able to select all
 possible samples, the estimates from each sample would differ, but the
 average of these estimates would approximate the complete-count figure.  The
 deviation of a particular sample estimate from the average value obtainable
 from all possible samples is called the sampling error.  The standard error
 of a survey estimate is a measure of the variation among the estimates from
 the possible samples and thus is a measure of the precision with which an
 estimate from a particular sample approximates the average result of all
 possible samples.  The sample estimate and its estimated standard error
 permit the user to construct an interval estimate having prescribed
 confidence that the interval includes the average result of all possible
 samples.  The method of calculating standard errors and confidence intervals
 for the estimates produced from the microdata samples is given below.

 In addition to the variability which arises from the sampling procedures,
 both sample data and complete-count data are subject to nonsampling error.
 Nonsampling error may be introduced during each of the many extensive and
 complex operations used to collect and process census data.  For example,
 operations such as editing, reviewing, or handling questionnaires may
 introduce error into the data.  Nonsampling error may affect the data in two
 ways.  Errors that are introduced randomly will increase the variability of
 the data, and should therefore be reflected in the standard error.  Errors
 that tend to be consistent in one direction will make both sample and
 complete-count data biased in that direction.  For example, if respondents
 consistently tend to underreport their income, then the resulting counts of
 households or families by income category will be skewed toward the low
 income categories.  Such biases are not reflected in the standard error.  A
 more detailed discussion of the sources of nonsampling error is given in the
 section "Control of Nonsampling Error" in this chapter.

 Calculation of Standard Errors Using Tables

 Two methods are presented for calculating standard errors of estimated totals
 and percentages.  (The procedures for estimating totals and percentages
 themselves were given in the previous chapter (page 14).)  The first method,
 described below, used tabled figures or simple formulas and produces an
 approximate standard error quickly and inexpensively.  The second method
 (presented on page 27) requires extra tabulations by the user during the
 processing of the microdata file, but it produces more precise standard
 errors and is the preferred method.  There are, of course, situations where
 it is not feasible to do the extra tabulations required by the second method,
 for instance, when one is trying to determine, prior to purchase, whether a
 one-percent sample will yield estimates of adequate precision for a given
 study or whether it is necessary to use the 5-percent sample instead.  For
 these purposes the method described in this section should produce an
 acceptable approximation.  On the other hand, for many statistics,
 particularly from detailed crosstabulations, standard errors using the second
 method should be substantially better.  The second method is also applicable
 to a wider variety of statistics, e.g., means and ratios.

 Tables A through G in this chapter contain the information necessary to
 calculate an approximate standard error of sample estimates.  In order to
 perform this calculation, one obtains (1) the unadjusted standard error for
 the characteristic that would result under a simple random sample design (of
 persons, families, or housing units) and estimation technique; and (2) an
 adjustment factor, which partially reflects the effects of the actual sample
 design and estimation procedure used for the 1980 census public-use microdata
 samples, for the particular characteristic estimated.  The adjustment factors
 provided in this chapter are based on computations from the full census
 sample and as such do not reflect the additional stratification used in the
 selection of the public-use microdata samples (see chapter 4).  Thus, in
 general, these factors will provide conservative estimates of the standard
 error.  In addition, these factors only pertain to individual data items
 (e.g., years of school completed, labor force status) and as such are not
 entirely appropriate for use with detailed cross-tabulated data.

 To calculate the approximate standard error of a 5-percent, 1-percent, or
 0.1-percent sample estimate follow the steps given below:

 a.  Obtain the unadjusted standard error for the sampling rate to be used
     from Table A, C, or E for estimated totals or from Table B, D, or F for
     estimated percentages.  Alternatively, the formula given at the bottom of
     each table may be used to calculate the unadjusted standard error.  (For
     sample sizes, other than 5, 1, or 0.1 percent, see page 26).

     In using Tables A, C, or E or corresponding formulas for estimated totals
     use weighted figures rather than raw sample counts to select the
     applicable row.  To select the applicable column for person
     characteristics, use the total population in the area being tabulated
     (not just the total of the universe being examined), or use the total
     count of housing units if the estimated total is a housing
     characteristic.  Similarly in using Tables B, D, or F or the
     corresponding formula for estimated percentages, use inflated figures to
     select the appropriate column.

 b.  Use Table G to obtain the factor for the characteristic (e.g., work
     disability, years of school completed).  If the estimate is a cross-
     tabulation of more than one characteristic scan Table G for each
     applicable factor and use the largest factor.  Multiply the unadjusted
     standard error from step a. by the factor obtained in step b.

 Example 1:  Standard error of a total - suppose we tally a 1% public-use
 microdata sample for Alaska and find 358 persons in the sample who are 18
 years and over and speak a language other than English at home.  Therefore,
 the weighted number of persons who are 18 years and over and speak a language
 other than English at home is 358 x 100 = 35,800.

 The unadjusted standard error for the estimated total is obtained from Table
 C or from the formula below Table C.  In order to avoid interpolation, the
 use of the formula will be demonstrated here.  The formula for the unadjusted
 standard error, Se, is



          Se(Y)       =   99Y (1-Y/N)


                                            35,800
          Se (35,800) =   99 (35,800) (1 - 401,851) = 1,797 persons.

 Note, in this example the complete census count of persons in Alaska of
 401,851 was used.  The standard error of the estimated 35,800 persons 18
 years and over who speak a language other than English at home is found by
 multiplying the unadjusted standard error, 1,797, by the appropriate
 adjustment factor.  The adjustment factor for "Language Usage and the Ability
 to speak English" given in Table G is 1.5.  Thus, the estimated standard
 error is 1,797 x 1.5 or 2,696.

 Example 2:  Standard error of a percent - To illustrate the calculation of
 the standard error of a percent, suppose the estimated percent of persons 18
 years and over who speak a language other than English at home who speak
 English "not well" or "not at all" is 12.7 (the estimated total persons 18
 years and over who speak a language other than English at home used as the
 base is 35,800).  Using Table D, and interpolating among the nearest figures,
 the unadjusted standard error is found to be approximately 0.53 and using the
 same adjustment factor, the standard error for the estimated 12.7 percent is
 0.53 x 1.5 = 0.795 percentage points.

 A note of caution concerning numerical values is necessary.  Standard errors
 derived in this manner are approximate.  Calculations could be expressed to
 several decimal places, but to do so would suggest more precision in the data
 then is justifiable.  One useful rule of thumb is to round standard error
 estimates to two significant digits.  Thus, 2,696 would be rounded to 2,700
 and 0.795 percentage points would be rounded to 0.80 percentage points.

 Table A - Unadjusted Standard Errors for Estimated Totals, 5 Percent Sample

 Estimated               Size of Geographic Area Tabulated2
   Total1      50,000  100,000  250,000  500,000  1 Million  5 Million

      1,000       140      140      140      140        140        140
      2,500       210      220      220      220        220        220
      5,000       290      300      310      310        310        310
     10,000       390      410      430      430        430        440
     15,000       450      490      520      530        530        530
     25,000       490      600      650      670        680        690
     75,000        -       600    1,000    1,100      1,150      1,180
    100,000        -        -     1,070    1,230      1,310      1,360
    250,000        -        -        -     1,540      1,890      2,120
    500,000        -        -        -        -       2,180      2,920
  1,000,000        -        -        -        -          -       3,900
  5,000,000        -        -        -        -          -          -
 10,000,000        -        -        -        -          -          -

               10 Million   25 Million

      1,000           140          140
      2,500           220          220
      5,000           310          310
     10,000           440          440
     15,000           530          530
     25,000           690          690
     75,000         1,190        1,190
    100,000         1,370        1,380
    250,000         2,150        2,170
    500,000         3,000        3,050
  1,000,000         4,140        4,270
  5,000,000         6,890        8,720
 10,000,000            -        10,680

 1 For estimated totals larger than 10,000,000, the standard error is somewhat
   larger than the table values.  The formula given below should be used to
   calculate the standard error.


                                 Where:
           Se(Y) =     99Y (1-Y)   N = Size of area
                              N
                                   Y = Estimate of characteristic total


 2 Total count of persons, housing units, or families in area if the estimated
   total is a person, housing unit, or family characteristic, respectively.




 Table B - Unadjusted Standard Error for Estimated Percentages, 5 Percent
           Sample
            (Standard errors expressed in percentage points)

 Estimated                Base (Weighted Total) of Percentage 1
  Percent   1,000  1,500  2,500  5,000  7,500  10,000  25,000  50,000  100,000

  2 or 98     1.9    1.6    1.2    0.9    0.7     0.6     0.4     0.3      0.2
  5 or 95     3.0    2.4    1.9    1.3    1.1     1.0     0.6     0.4      0.3
 10 or 90     4.1    3.4    2.6    1.8    1.5     1.3     0.8     0.6      0.4
 15 or 85     4.9    4.0    3.1    2.2    1.8     1.6     1.0     0.7      0.5
 20 or 80     5.5    4.5    3.5    2.5    2.0     1.7     1.1     0.8      0.6
 25 or 75     6.0    4.9    3.8    2.7    2.2     1.9     1.2     0.8      0.6
 30 or 70     6.3    5.2    4.0    2.8    2.3     2.0     1.3     0.9      0.6
 35 or 65     6.6    5.4    4.2    2.9    2.4     2.1     1.3     0.9      0.7
    50        6.9    5.6    4.4    3.1    2.5     2.2     1.4     1.0      0.7

            250,000  500,000

  2 or 98       0.1      0.1
  5 or 95       0.2      0.1
 10 or 90       0.3      0.2
 15 or 85       0.3      0.2
 20 or 80       0.3      0.2
 25 or 75       0.4      0.3
 30 or 70       0.4      0.3
 35 or 65       0.4      0.3
    50          1.4      0.3

 1 For a percentage and/or base of percentage not shown in the Table, the
   formula given below may be used to calculate the standard error.


                                      Where:
           Se(p) =     19               B = Base of estimated percentage
                        B p (100-p)                (weighted total)
                                        p = Estimated percentage

 Table C - Unadjusted Standard Errors for Estimated Totals, 1 Percent Sample

 Estimated               Size of Geographic Area Tabulated2
   Total1      50,000  100,000  250,000  500,000  1 Million  5 Million

      1,000       310      310      310      310        310        310
      2,500       480      490      500      500        500        500
      5,000       670      690      700      700        700        700
     10,000       890      940      970      980        990        990
     15,000     1,020    1,120    1,180    1,200      1,210      1,220
     25,000     1,110    1,360    1,490    1,530      1,550      1,570
     75,000        -     1,360    2,280    2,510      2,620      2,700
    100,000        -        -     2,440    2,810      2,980      3,110
    250,000        -        -        -     3,520      4,310      4,850
    500,000        -        -        -        -       4,970      6,670
  1,000,000        -        -        -        -          -       8,900
  5,000,000        -        -        -        -          -          -
 10,000,000        -        -        -        -          -          -

               10 Million   25 Million

      1,000           310          310
      2,500           500          500
      5,000           700          700
     10,000           990          990
     15,000         1,220        1,220
     25,000         1,570        1,570
     75,000         2,710        2,720
    100,000         3,130        3,140
    250,000         4,910        4,950
    500,000         6,860        6,960
  1,000,000         9,440        9,750
  5,000,000        15,730       19,900
 10,000,000            -        24,370

 1 For estimated totals larger than 10,000,000, the standard error is somewhat
   larger than the table values.  The formula given below should be used to
   calculate the standard error.


                                 Where:
           Se(Y) =     99Y (1-Y)   N = Size of area
                              N
                                   Y = Estimate of characteristic total

 2 Total count of persons, housing units, or families in area if the estimated
   total is a person, housing unit, or family characteristic, respectively.





 Table D - Unadjusted Standard Error for Estimated Percentages, 1 Percent
           Sample
             (Standard errors expressed in percentage points)

 Estimated                Base (Weighted Total) of Percentage1
  Percent   1,000  1,500  2,500  5,000  7,500  10,000  25,000  50,000  100,000

  2 or 98     4.4    3.6    2.8    2.0    1.6     1.4     0.9     0.6      0.4
  5 or 95     6.9    5.6    4.3    3.1    2.5     2.2     1.4     1.0      0.7
 10 or 90     9.4    7.7    6.0    4.2    3.4     3.0     1.9     1.3      0.9
 15 or 85    11.2    9.2    7.1    5.0    4.1     3.6     2.2     1.6      1.1
 20 or 80    12.6   10.3    8.0    5.6    4.6     4.0     2.5     1.8      1.3
 25 or 75    13.6   11.1    8.6    6.1    5.0     4.3     2.7     1.9      1.4
 30 or 70    14.4   11.8    9.1    6.4    5.3     4.6     2.9     2.0      1.4
 35 or 65    15.0   12.8    9.5    6.7    5.5     4.7     3.0     2.1      1.5
    50       15.8   12.8    9.9    7.0    5.7     5.0     3.1     2.2      1.6

            250,000  500,000

  2 or 98       0.3      0.2
  5 or 95       0.4      0.3
 10 or 90       0.6      0.4
 15 or 85       0.7      0.5
 20 or 80       0.8      0.6
 25 or 75       0.9      0.6
 30 or 70       0.9      0.6
 35 or 65       0.9      0.7
    50          1.0      0.7

 1 For a percentage and/or base of percentage not shown in the Table, the
   formula given below may be used to calculate the standard error.


                                      Where:
           Se(p) =     99               B = Base (weighted total) of estimated
                        B p (100-p)                percentage
                                        p = Estimated percentage

 Table E - Unadjusted Standard Errors for Estimated Totals, 0.1 Percent Sample

 Estimated               Size of Geographic Area Tabulated2
   Total1      50,000  100,000  250,000  500,000  1 Million  5 Million

      1,000       990      990    1,000    1,000      1,000      1,000
      2,500     1,540    1,560    1,570    1,580      1,580      1,580
      5,000     2,120    2,180    2,210    2,220      2,230      2,230
     10,000     2,830    3,000    3,100    3,130      3,140      3,160
     15,000     3,240    3,570    3,750    3,810      3,840      3,870
     25,000     3,530    4,330    4,740    4,870      4,930      4,980
     75,000        -     4,330    7,240    7,980      8,330      8,590
    100,000        -        -     7,740    8,940      9,480      9,980
    250,000        -        -        -    11,170     13,690     15,400
    500,000        -        -        -        -      15,800     21,200
  1,000,000        -        -        -        -          -      28,270
  5,000,000        -        -        -        -          -          -
 10,000,000        -        -        -        -          -          -

               10 Million   25 Million

      1,000         1,000        1,100
      2,500         1,580        1,580
      5,000         2,230        2,230
     10,000         3,160        3,160
     15,000         3,870        3,870
     25,000         4,990        5,000
     75,000         8,620        8,640
    100,000         9,940        9,970
    250,000        15,600       15,720
    500,000        21,780       22,120
  1,000,000        29,980       30,970
  5,000,000        49,970       63,210
 10,000,000            -        77,420

 1 For estimated totals larger than 10,000,000, the standard error is somewhat
   larger than the table values.  The formula given below should be used to
   calculate the standard error.


                                  Where:
           Se(Y) =     999Y (1-Y)   N = Size of area
                               N
                                    Y = Estimate of characteristic total

 2 Total count of persons, housing units, or families in area if the estimated
   total is a person, housing unit, or family characteristic, respectively.


 Table F - Unadjusted Standard Error for Estimated Percentages, 0.1 Percent
           Sample
             (Standard errors expressed in percentage points)

 Estimated                Base (Weighted Total) of Percentage1
  Percent    1,500   2,500   5,000   7,500  10,000  25,000  50,000  100,000

  2 or 98     11.4     8.8     6.3     5.1     4.4     2.8     2.0     1.4
  5 or 95     17.8    13.8     9.7     8.0     6.9     4.4     3.1     2.2
 10 or 90     24.5    19.0    13.4    10.9     9.5     6.0     4.2     3.0
 15 or 85     29.1    22.6    16.0    13.0    11.3     7.1     5.0     3.6
 20 or 80     32.6    25.3    17.9    14.6    12.6     8.0     5.7     4.0
 25 or 75     35.3    27.4    19.4    15.8    13.7     8.7     6.1     4.3
 30 or 70     37.4    29.0    20.5    16.7    14.5     9.2     6.5     4.5
 35 or 65     38.9    31.2    21.3    17.4    15.1     9.5     6.7     4.8
    50        40.8    31.6    22.3    18.2    15.8    10.0     7.1     5.0

            250,000  500,000

  2 or 98       0.9      0.6
  5 or 95       1.4      1.0
 10 or 90       1.9      1.3
 15 or 85       2.3      1.6
 20 or 80       2.5      1.8
 25 or 75       2.7      1.9
 30 or 70       2.9      2.0
 35 or 65       3.0      2.1
    50          3.2      2.2

 1 For a percentage and/or base of percentage not shown in the Table, the
   formula given below may be used to calculate the standard error.


                                      Where:
           Se(p) =     999               B = Base (weighted total) of
                        B  p (100-p)                estimated percentage
                                         p = Estimated percentage

 Table G:  Standard Error Adjustment Factors

 Characteristic                                                         Factor

 POPULATION
 Urban and Rural                                                          1.0
 Age, Sex, Race, and spanish Origin                                       1.2
 Household Type                                                           1.1
 Household Relationship                                                   1.3
 Household Size                                                           1.1
 Marital Status                                                           1.0
 Language Usage and Ability to Speak English                              1.5
 Ancestry                                                                 1.7
 Type of Group Quarters                                                   0.9
 Citizenship, Place of Birth, and Year of Immigration                     2.1
 Residence in 1975                                                        3.6
 Place of Work                                                            2.2
 Travel Time to Work                                                      1.8
 Means of Transportation to Work and Private Vehicle Occupancy            1.3
 School Enrollment                                                        1.5
 Years of School Completed                                                1.2
 Veteran Status and Period of Service                                     1.1
 Work & Public Transportation Disability                                  1.2
 Labor Force Status                                                       1.3
 Hours Worked Per Week and Weeks Worked in 1979                           1.2
 Unemployment in 1979                                                     1.2
 Industry and Occupation                                                  1.2
 Class of Worker                                                          1.3
 Household Income                                                         1.1
 Income Type                                                              1.3
 Family Income                                                            1.1
 Unrelated Individual Income                                              1.2
 Workers in Family                                                        1.3
 Poverty Status - Family                                                  1.1
 Poverty Status - Persons                                                 2.0
 Poverty Status - Unrelated Individuals                                   1.2

 HOUSING
 Occupancy and Vacancy Status                                             1.1
 Tenure                                                                   1.1
 Units in Structure                                                       1.1
 Stories in Structure                                                     1.0
 Passenger Elevator                                                       1.0
 Source of Water                                                          1.1
 Sewage Disposal                                                          1.1
 Year Structure Built                                                     1.1
 Year Householder Moved Into Housing Unit                                 1.1
 Heating Equipment and Fuels                                              1.2
 Kitchen or Plumbing Facilities                                           1.1
 Number of Rooms, Bedrooms, or Bathrooms                                  1.1
 Telephone in Housing Unit                                                1.1
 Air Conditioning                                                         1.1
 Vehicles Available                                                       1.1
 Gross Rent, Contract Rent, or Value                                      1.1
 Inclusion of Utilities in Rent                                           1.1
 Mortgage Status and Selected Monthly Owner Costs                         1.1

 Confidence Intervals and Inferences Based on the Sample

 A sample estimate and its estimated standard error may be used to construct
 confidence intervals about the estimate.  These intervals are ranges that
 will contain, with a known probability, the value of the estimated
 characteristic that would be obtained by averaging the estimates from all
 possible samples.  For example, if all possible samples that could result
 under the 1980 public-use microdata sample design were independently selected
 and surveyed under the same conditions, and if the estimate and its estimated
 standard error were calculated for each of these samples, then:

 (1)  Approximately 68 percent of the intervals from one estimated standard
      error below the estimate to one estimated standard error above the
      estimate would contain the average result from all possible samples; and

 (2)  Approximately 95 percent of the intervals from two estimated standard
      errors below the estimate to two estimated standard errors above the
      estimate would contain the average result from all possible samples.

 The intervals are referred to as 68-percent and 95-percent confidence
 intervals, respectively.

 One may be tempted to think of a confidence interval in terms such as these:
 that the number we are trying to estimate, the average value calculated over
 all possible samples, has a given probability of falling between the upper
 and lower limits of that interval.  Actually, this is not technically
 correct, since the average estimate from all possible samples already exists,
 though its value is unknown, and it remains the same regardless of which of
 the possible samples we select.  Rather, it is the confidence interval which
 varies from sample to sample.  Thus, one can say, with a specified
 probability or level of confidence, that the confidence interval, as
 calculated from the particular sample selected, includes the average estimate
 from all possible samples.

 Confidence intervals may also be constructed for the difference between two
 sample figures.  This is done by computing the difference between these
 figures, obtaining the standard error of the difference and then forming a
 confidence interval for this estimated difference as above.  For the
 difference between two sample estimates (totals or percentages), the standard
 error is approximately the square root of the sum of the standard errors for
 each estimate squared; that is for standard errors Se(x) and Se( ) of
 estimated tools x and  , the standard error of the differences between x and
   is:


                                 2          2
          Se(x - y) =     (Se(x))  + (Se(y))

 The formula for the standard error between two percentages is similarly
 defined.

 This method will, however, overestimate the standard error if the two
 estimates (x and  ) are positively correlated, or underestimate the standard
 error if they are negatively correlated.

 Example 3:  Confidence interval for a total - To illustrate the calculation
 of a confidence interval consider the previous example, where the standard
 error of the estimated 35,800 persons in Alaska who were 18 years and over
 who speak a language other than English was found to be 2,700.  An
 approximate 95-percent confidence interval for this estimated total is
 obtained by adding and subtracting twice the standard error from the
 estimated total.  In this example, the 95-percent confidence interval is:

          35,800 - 2 (2,700)  to  35,800 + 2 (2,700)
                             -or-
                     30,400   to  41,200

 One can say with about 95-percent confidence that this interval includes the
 value that would have been obtained by averaging the estimates obtainable
 from all possible samples.

 Selecting an appropriate sample size - One virtue in the use of Tables A to G
 for calculating standard errors and confidence intervals is that this method
 can be employed prior to making any sample tabulations, and thus can help the
 user decide prior to purchase whether a 5-percent, 1-percent or 0.1-percent
 sample size is most appropriate for a proposed study.  Suppose that, in the
 foregoing example, the 35,800 figure was a guess, perhaps based on published
 data.  The confidence interval could be calculated as above.  In this case,
 it is apparent that tabulating a 1-percent sample for this particular
 characteristic would result in a rather broad confidence interval:  30,400 to
 41,200.  On the other hand, if one assumed that tabulations will be made
 using a 5-percent sample instead, the confidence interval could be
 recalculated using Table A, and found to be to 33,000 to 38,200, a much
 narrower range.  There is no particular rule of thumb that dictates how large
 a confidence interval is acceptable:  this depends on the relative precision
 necessary for a particular application as balanced against the relative cost
 of tabulating microdata samples of the various sizes.

 Example 4:  Confidence interval for a difference - The use of standard errors
 and confidence intervals can also be illustrated for a difference of two
 estimated percentages.  Suppose that, from a 1% microdata sample for Hawaii,
 we tally 1,997 persons 18 years and over who speak a language other than
 English at home, of whom 395 speak English "not well" or "not at all".  Thus,
 the percentage of persons 18 years and over who speak a language other than
 English at home who speak English "not well" or "not at all" is 19.8 percent.
 The unadjusted standard error interpolated from Table D (using 199,700 as the
 base of the percentage) is 0.96 percent.  The adjustment factor is 1.5 for
 "Language Usage and the Ability to Speak English" and the approximate
 standard error of the percentage (19.8 percent) is 0.96 x 1.5 = 1.4
 percentage points.

 The difference between the percentages of persons in Alaska and Hawaii who
 are 18 years and over who speak a language other than English at home, who
 speak English "not well" or "not at all" is

          19.8 - 12.7 = 7.1 percent.

 The standard error of the difference, Se(7.1), is



                                   2              2
          Se(7.1)  =     (Se(19.8))  +  (Se(12.7))


                              2         2
                   =     (1.4)  + (0.80)


                   =     1.6 percent.

 The 95-percent confidence interval for the difference is formed as before and
 is

          7.1 - 2 (1.6)  to  7.1 + 2 (1.6)
                        -or-
                   3.9   to  10.3.

 One can say with 95-percent confidence that the interval includes the
 difference that would have been obtained by averaging the results from all
 possible samples.  When, as in this example, the interval does not include
 zero, one can conclude, again with 95-percent confidence, that the difference
 observed between the two States on this characteristic is greater than can be
 attributed to sampling error.

 Adjusting Tables A Through F for Other Sample Sizes

 Tables A through F may also be used to approximate the unadjusted standard
 errors for other sample sizes by adjusting for the sample size desired.  The
 adjustment for sample size is obtained as follows:

          let:
           f1 be the sampling rate shown in any of Tables A through F.
           f2 be the sampling rate for the sample size to be used.

 Then the adjustment for sample size can be read from the following table.

      f2                   Sample Size Adjustment Factor

      0.07          0.84

      0.06          0.91
                                 Multiply the standard
      0.04          1.12         errors in tables A or B
                                 (where f1 = 0.05)
      0.03          1.30         by this factor.

      0.02          1.61



      0.009         1.06

      0.007         1.20         Multiply the standard
                                 errors in tables C or D
      0.005         1.42         (where f1 = 0.01)
                                 by this factor.
      0.003         1.83

      0.002         2.25



      0.0009        1.05         Multiply the standard
                                 errors in tables E or F
      0.0005        1.41         (where f1 = 0.001)
                                 by this factor.
      0.0001        3.16



 For example, if the user were to select a subsample of one half of a one-
 percent sample, i.e., f2 = 0.005, then the standard errors shown in Table C
 or D for a one-percent sample must be multiplied by 1.42 to obtain the
 standard errors for a 0.005 sample.  The factor of 1.42 shows that the
 standard errors increase by 42 percent when the sample size is halved.
 (Although migration, place of work and travel time data are available only
 for one half of the sample, it is not necessary to multiply standard errors
 for those figures by 1.42, since the sample reduction is already reflected in
 the factors in Table G).

 The principle is also applicable when combining microdata samples to achieve
 a sample size larger than five percent.  If, for instance, all three samples
 are combined for the same area, the standard errors for this sample size
 (i.e., seven percent) can be obtained by multiplying those shown in Tables A
 and B by 0.84.  Thus, the increase from a 5-percent to a 7-percent sample
 reduces the standard error by approximately sixteen percent.

 Alternatively, the user may wish to use the following formulas to directly
 calculate the unadjusted standard errors.

 For estimated totals, calculate


                                             Where:
          Se(Y) =     (1  - 1) Y (1-Y/N)        N = size of area tabulated
                       f2
                                                Y = estimate (weighted) of
                                                      characteristic total

 For estimated percentages, calculate




                                             Where:
          Se(p) =     (1  - 1) p(100-p)
                       f2         B            p = estimated percentage
                                               B = base of estimated
                                                     percentage (weighted
                                                     estimate)

 Estimation of Standard Errors Directly From the Microdata Samples

 Use of tables or formulas to derive approximate standard errors as discussed
 above is simple, inexpensive, and does not complicate processing.
 nonetheless, a more accurate estimate of the standard error can be obtained
 from the samples themselves using the random group method.  Using this method
 it is also possible to compute standard errors for means, ratios, indexes,
 correlation coefficients, or other statistics for which the tables or
 formulas presented earlier do not apply.

 The random group method does increase processing costs somewhat since it
 requires that the statistic of interest, for example a total, be computed
 separately for each of up to 100 random groups.  The variability of that
 statistic for the sample as a whole is estimated from the variability of the
 statistic among the various random groups within the sample.  The procedure
 for calculating a standard error by the random group method for various
 statistics is given below.

 Totals - to obtain the standard errors of estimated totals, the following
 method should be used.



         1
 Let x = f (x) be the estimated total

 Where:
   f  = the sampling fraction for the sample size used
        (e.g., f = .05 for a 5 percent sample); and
  (x) = the unweighted microdata sample total of the characteristic
        of interest.

 Then the random groups estimate of the variance of x is given by

                      2   t          t     2
                t    1       +xg-1/t(   xg)+
     Var(x) = (t-1) (f)  g=1        g=1

 Where:
   t  = the number of random groups selected; and
   xg = the unweighted microdata sample total of the characteristic
        of interest from the gth random group.

 The standard error of the estimated total = the square root of the estimated
 variance.

 It is suggested that t=100 for estimating the standard error of a total
 since, as discussed in chapter 4, each of the A, B and C Sample records was
 assigned a two-digit subsample number consecutively from 00 to 99.  This two-
 digit number can be used to form the 100 random groups.  For example, all
 sample cases with 01 as the two-digit number will be in random group 1, all
 sample cases with 02 as the two-digit number will be in random group 2, etc.,
 up to 00 as the one-hundredth random group.  Use of t = 100 will also provide
 maximum reliability of the estimated standard errors.

 Percentages, Ratios and Means

 Percentages, Ratios and Means - To obtain the estimated standard error of a
 percent, ratio, or mean, the following method should be used.


 Let r = x/y be the estimated percent, ratio, or mean

 Where:

   x and y = the estimated totals as defined above for the x and y
             characteristics.

 For the case where both numerator and denominator are obtained from the full
 microdata sample (i.e., all data items except place of work, travel time to
 work and migration) or from the migration/place of work half sample, the
 random groups estimate of the variance of   is given by
                                           r

                      2   t            2
                t    1       (xg - ryg)
     Var(r) = (t-1) (y)  g=1

 Where:
   t and xg are as defined above,
   y   = the unweighted full microdata sample total for the y characteristic;
         and
   yg  = the corresponding unweighted total for the gth random group.

 If the percentage, ratio, or mean is estimated by using the migration/place
 of work half sample for the numerator characteristic, and the full microdata
 sample for the denominator characteristic, then the random group variance
 estimator is as follows:

                      2   t             2
                t    1       (2xg - ryg)
     Var(r) = (t-1) (y)  g=1

 Where:
   All terms are as previously defined--again, use of t = 100 is recommended.

 Correlation Coefficients, and Regression Coefficients

 Correlation Coefficients, and Regression Coefficients and Other Complex
   Statistics - The random group method for computing the variance of
 correlation coefficients, regression coefficients, and other complex
 nonlinear statistics can be expressed as:

                       t          2
                 1        (0g - 0)
     Var(0) = t(t-1)  g=1

 Where:

   0g = the weighted estimate (at the tabulation area level) of the statistic
          of interest computed from the gth random group; and

   0  = corresponding weighted estimate computed from the full microdata
          sample.

 Care must be exercised when using this variance estimator for complex
 nonlinear statistics as its properties have not been fully explored for such
 statistics.  In particular, the choice of the number of random groups to be
 used must be considered more carefully.  When using the 5 percent sample, use
 of t = 100 for all areas tabulated is recommended.  When using the 1-percent
 sample or samples having a smaller sampling fraction, the user should
 consider using a smaller number of random groups to insure that each random
 group contains at least 25 records.  Fewer than 100 random groups can be
 formed by appropriate combination of the two digit subsample numbers.  For
 example, to construct fifty random groups assign all records in which the
 subsample number is 01 or 51 to the first random group; all records in which
 the subsample number is 02 or 52 to the second random group, etc.  Finally,
 assign all records in which the subsample number is 00 or 50 to random group
 50.  Ten random groups can be constructed by including all records having
 subsample numbers with the same "units" digit in a particular random group.
 For example, subsample numbers 00,10,20,..., 90 would form one random group;
 subsample numbers 01,11,...,91 would form a second random group, etc.  A more
 extensive discussion of the considerations leading to the proper choice of
 the number and size of the random groups is given in Hansen, Hurwitz and
 Madow, Sample Surveys Methods and Theory, Vol. 1, Chapter 10, section 16,
 page 440 ff.

 Medians

 Medians - The random group method given above is not applicable to a sample
 median.  Assuming the user has calculated the median from the individual
 sample observations, an approximate 95-percent confidence interval can be
 obtained by counting  n observations to the left and right of the sample
 median value,

 Where:
  n = the raw sample count of the number of observations on which the median
        is based; and,
  median = the value of the n/2 observation.

 Thus, the upper and lower limits of the confidence interval are the values
 for the (n/2 +  n) observation and (n/2 -  n) observation.

 Additional Notes On Standard Errors

 Two additional points concerning the standard errors calculated by the random
 group method presented in this section are important.  First, the estimated
 standard errors obtained from this procedure do not include all portions of
 the variability due to nonsampling error that may be present in the data.
 Thus, the calculated standard errors represent a lower bound of the total
 error.  As a result, confidence intervals formed using these estimated
 standard errors may not meet the stated levels of confidence (e.g., 68 or 95-
 percent).  Thus, some care must be exercised in the analysis of the microdata
 sample data based on the estimated standard errors from the random groups
 procedure.

 Second, percentage estimates of zero and estimated totals of zero are subject
 to both sampling and nonsampling error.  While the magnitude of the error is
 difficult to quantify, the user should be aware that such estimates are
 nevertheless subject to both sampling and nonsampling error even though in
 the case of zero estimates the corresponding random groups estimate of the
 standard error will be zero.

 Control of Nonsampling Error

 As mentioned above, nonsampling error is present in both sample and complete-
 count data.  If left unchecked, this error could introduce serious bias into
 the data, the variability of which could increase dramatically over that
 which would result purely from sampling.  While it is impossible to
 completely eliminate nonsampling error from an operation as large and complex
 as the 1980 census, the Bureau of the Census attempted to control the sources
 of such error during the collection and processing operations.  The primary
 sources of nonsampling error and the programs instituted for control of this
 error are described below.  The success of these programs, however, was
 contingent upon how well the instructions were actually carried out during
 the census.  To the extent possible, both the effects of these programs and
 the amount of error remaining after their application will be evaluated.

 Undercoverage--It is possible for some housing units or persons to be
 entirely missed by the census.  This undercoverage of persons and housing
 units can introduce biases into the data.  Several extensive programs were
 developed to focus on this important problem.

        The Postal Service reviewed mailing lists and reported housing unit
        addresses which were missing, undeliverable, or duplicated in the
        listings.

        The purchased commercial mailing list was updated and corrected by a
        complete field review of the list of housing units during a precanvass
        operation.

        A record check was performed to reduce the undercoverage of individual
        persons in selected areas.  Independent lists of persons, such as
        driver's license holders, were matched with the household rosters in
        the census listings.  Persons not matched to the census rosters were
        followed up and added to the census counts if they were found to have
        been missed.

        A recheck of housing units initially classified as vacant or non-
        existent was utilized to further reduce the undercoverage of persons.

 More extensive discussions of programs developed to reduce undercoverage will
 be published as the analyses of those programs are completed.

 Respondent and Enumerator Error - The person answering the questionnaire or
 responding to the questions posed by an enumerator could serve as a source of
 error by offering incorrect or incomplete information.  To reduce this source
 of error, questions were phrased as clearly as possible based on precensus
 tests, and detailed instructions for completing the questionnaire were
 provided to each housing unit.  In addition, respondents' answers were edited
 for completeness and consistency and followed up as necessary.  For example,
 if labor force items were incomplete for a person 15 years and over, long-
 form field edit procedures would recognize the situation and a follow-up
 attempt to obtain the information would be made.

 The enumerator may misinterpret or otherwise incorrectly record information
 given by a respondent; may fail to collect some of the information for a
 person or housing unit; or may collect data for housing units that were not
 designated as part of the sample.  To control these problems, the work of
 enumerators was carefully monitored.  Field staff were prepared for their
 tasks by using standardized training packages which included experience in
 using census materials.  A sample of the housing units interviewed by
 enumerators for nonresponse were reinterviewed to control for the possibility
 of data for fabricated persons being submitted by enumerators.  Also, the
 estimation procedure was designed to control for biases that would result
 from the collection of data from housing units not designated for the sample.

 Processing Error - The many phases of processing the census represent
 potential sources for the introduction of nonsampling error.  The processing
 of the census questionnaires includes the field editing, follow-up, and
 transmittal of completed questionnaires; the manual coding of write-in
 responses; and the electronic data processing.  The various field, coding and
 computer operations undergo a number of quality control checks to insure
 their accurate application.

 Nonresponse - Nonresponse to particular questions on the census questionnaire
 allows for the introduction of bias into the data, since the characteristics
 of the nonrespondents have not been observed and may differ from those
 reported by respondents.  As a result, any allocation procedure using
 respondent data may not completely reflect this difference either at the
 element level (individual person or housing unit) or on the average.  Some
 protection against the introduction of large biases is afforded by minimizing
 nonresponse.  In the census, nonresponse was substantially reduced during the
 field operations by the various edit and follow-up operations aimed at
 obtaining a response for every question.  Characteristics of the nonresponses
 remaining after this operation were allocated by computer as discussed below.

 Editing of Unacceptable Data

 The objective of the processing operation is to produce a set of statistics
 that describes the population as accurately and clearly as possible.  To meet
 this objective, certain unacceptable entries were edited.

 In the field, questionnaires were reviewed for omissions and certain
 inconsistencies by a census clerk or an enumerator and, if necessary, as
 follow-up was made to obtain missing information.  In addition, a similar
 review of questionnaires was done in the central processing offices.  As a
 rule, however, editing was performed by hand only when it could not be done
 effectively by machine.

 As one of the first steps in editing, the configuration of marks on the
 questionnaire column was scanned electronically to determine whether it
 contained information for a person or merely spurious marks.  If the column
 contained entries for at least two of the basic characteristics
 (relationship, sex, race, age, marital status, Spanish origin), the inference
 was made that the marks represented a person.  In cases in which two or more
 basic characteristics were available for only a portion of the people in the
 unit, other information on the questionnaire provided by an enumerator was
 used to determine the total number of persons.  Names were not used as a
 criterion of the presence of a person because the electronic scanning did not
 distinguish any entry in the name space.

 If any characteristics for a person were still missing when the
 questionnaires reached the central processing offices, they were supplied by
 allocation.  Allocations, or assignments of acceptable codes in place of
 unacceptable entries, were needed most often when the entry for the given
 item is lacking or when the information reported for a person on that item
 was inconsistent with entries for other persons with similar characteristics.

 Thus, a person who was reported as a 20-year-old son of the householder, but
 for whom marital status was not reported, was assigned the same marital
 status as that of the last son processed in the same age group.  The
 assignment of acceptable codes in place of blanks or unacceptable entries, it
 is believed, enhances the usefulness of the data.

 The 1980 census data on the economic questions such as industry, occupation,
 class of worker, work experience, and income were processed using an
 allocation system which assigned values to missing entries in these
 questions, as necessary, from a single respondent with similar socioeconomic
 characteristics.  In the 1970 census, allocation of each of the economic
 items was conducted separately; thus, assigned values could come from more
 than one respondent.

 Prior to the allocation of all economic variables, the computer records were
 sorted according to such characteristics as sex, race and ethnicity,
 household relationship, years of school completed, and geographic area.  The
 actual allocation operation was implemented in the following manner:

     1.  The computer stored, in a series of matrices, reported economic
         information of persons by selected characteristics such as age,
         disability status, presence of children, veteran's status, employment
         status, occupation, industry, class of worker status, work experience
         in 1979, level of earnings in 1979, and value of property or monthly
         rent.

     2.  The stored entries in the various matrices were retained in the
         computer only until a succeeding person having the same set of
         characteristics was processed through the computer.  Then the
         economic question responses of the succeeding person were stored in
         place of those previously stored.

     3.  When one or more of the economic questions was not reported, or the
         entry was unacceptable, the variables assigned to this person were
         those stored in the appropriate matrix for the last person who
         otherwise had the same set of characteristics.

 The use of this single allocation system ensured that the distribution of
 economic variable assignments would correspond closely to the entries of
 persons who had actually reported in the census.

 Specific tolerances were established for the number of computer allocations
 and substitutions that would be permitted.  If the number of corrections was
 beyond tolerance, the questionnaires in which the errors occurred were
 clerically reviewed.  If it was found that the errors resulted from damaged
 questionnaires, from improper microfilming, from faulty reading by FOSDIC of
 undamaged questionnaires, or from other types of machine failure, the
 questionnaires were reprocessed.

 The impact of the editing performed on 1980 census data can be gauged by
 reviewing allocation tables in selected reports based on the complete count-
 -PC80-1-B tables B-1 to B-4 and HC80-1-A tables A-1 and A-2-- and from the
 full census sample--PC80-1-C tables C-1 to C-5 and HC80-1-B tables B-2 and B-
 2.  Most of these tables provide rates of allocation for the various items.
 Two tables (PC80-1-B:B-1 and PC80-1-C:C-2) allow comparison of simple
 distributions as published (i.e., "after allocation") with corresponding
 distributions where missing values were not imputed (i.e., "before
 allocation").  An additional editing process, substitution, referred to in
 the complete-count reports, is not applicable to data from the full census
 sample or public-use microdata samples.

 Use of Allocation Flags in These Files

 As a result of the editing there are no blank fields or missing data in
 public-use microdata sample files.  Each field contains a data value or a
 "not applicable" indicator, except for the few items where allocation was not
 appropriate and a "not reported" indicator is included.  For every subject
 item it is possible for the user to differentiate between entries which were
 actually reported by the respondent and entries which were allocated, by
 means of "allocation flags" in terms H117 through H162 and P140 through P193
 in the microdata files.  For all items it is possible to compute the
 allocation rate and, if the rate is appreciable, to compute the distribution
 of actually observed values (with allocated data omitted) and compare it with
 the overall distribution including allocated values.

 Descriptions of many of the allocation flags indicate more than one possible
 type of allocation.  "Consistency edits" or "assignments" imputed missing
 characteristics based on other information recorded for the person or housing
 unit; for example, if the marital status was missing for a person with a
 reported relationship of husband/wife, the imputation of "married" was termed
 a consistency edit.  "Hot deck" allocation supplied the missing information
 from the record of another person or housing unit with similar
 characteristics.  "Cold deck" allocation, employed for only a few items,
 supplied missing information from a predetermined distribution; for example,
 a missing quarter of birth was assigned at random with equal probability
 given to each of the possible 4 categories.  Those flags designated "pre-
 edit" indicate that the original entry was rejected because it fell outside
 the range of acceptable values.

 In general, the allocation procedures provide better data than could be
 obtained by simply weighting up the observed distribution to account for
 missing values.  The procedures reflect local variations in characteristics
 as well as variation among the strata used in imputation.  There are,
 however, certain circumstances where allocated data may introduce undesirable
 bias.  It may be particularly important to analyze allocations of data in
 detailed studies of subpopulations or in statistics derived from cross-
 classification of variables, such as correlation coefficients or measures of
 regression.  The degree of editing required was greater for some subjects
 than for others.  While the allocation procedure was designed to yield
 appropriate statistics for the overall distribution or for specific
 subpopulations (the strata used in the allocation process), allocated
 characteristics will not necessarily preserve a valid relationship with other
 observed variables for the same individual.  For example, consider a
 tabulation of persons 80 years old and over by income.  Income allocations
 were made separately for different age groupings, including the category 65
 years old and over, but not separately for persons 80 years old and over.
 Since persons 65 to 70 or 75 are more likely to have significant earnings
 than persons 80 or over, allocated income data for the latter group would be
 biased upward.  Thus, if the rate of allocations for the group is appreciably
 large and a bias in the allocated values is evident, it may be desirable to
 exclude allocated data from the analysis.

 It should also be apparent from this illustration that knowledge of the
 specific allocation procedures is valuable in detailed subject analysis.
 Descriptions of the editing and allocation procedures for each item are
 being incorporated in the History of the 1980 Census of Population and
 Housing to be published in 1985.  An advance copy of the procedural
 descriptions for desired items can be requested from the Census History
 Staff, Data User Services Division, Bureau of the Census, Washington, D.C.
 20233.  A user may contact either Population Division or Housing Division,
 Bureau of the Census, if more information is desired on the allocation scheme
 for a specific subject item.
SAMPLE DESIGN FOR THE PUBLIC USE MICRODATA SAMPLES

 General Information

 This chapter discusses the selection procedure for the public-use microdata
 samples in terms of three major operations (1) the selection of the full 1980
 census sample, (2) the estimation procedure for the full census sample, and
 (3) the selection of the public-use microdata samples from the persons and
 housing units included in the full 1980 census sample, using weights derived
 from the full sample estimation procedure.

 1980 Census Sample Design and Estimation Procedure

 While every person and housing unit in the United States was enumerated on a
 questionnaire that requested certain basic demographic information (e.g.,
 age, race, relationship), a sample of persons and housing units was
 enumerated on a questionnaire that requested additional information.  The
 basic sampling unit for the 1980 census was the housing unit, including allz
 occupants.  For persons living in group quarters, the sampling unit was the
 person.  Two sampling rates were employed.  In counties, incorporated places
 and minor civil divisions estimated to have fewer than 2,500 persons (based
 on precensus estimates), one-half of all housing units and persons in group
 quarters were to be included in the sample.  In all other places, one-sixth
 of the housing units or persons in group quarters were sampled.  The purpose
 of this scheme was to provide relatively more reliable estimates for small
 places.  When both sampling rates were taken into account across the Nation,
 approximately 19 percent of the Nation's housing units were included in the
 census sample.

 The sample designation method depended on the data collection procedures.  In
 about ninety-five percent of the country the census was taken by the
 mailout/mailback procedure.  For these areas, the Bureau of the Census either
 purchased a commercial mailing list which was updated and corrected by Census
 Bureau field staff, or prepared a mailing list by canvassing and listing each
 address in the area prior to Census Day.  These lists were computerized, and
 every sixth unit (for 1-in-6 areas) or every second unit (for 1-in-2 areas)
 was designated as a sample unit by computer.  Both of these lists were also
 corrected by the Post Office.

 In non-mailout/mailback areas, a blank listing book with designated sample
 lines (every sixth or every second line) was prepared for the enumerator.
 Beginning about Census Day, the enumerator systematically canvassed the areas
 and listed all housing units in the listing book in the order they were
 encountered.  Completed questionnaires, including sample information for any
 housing unit which was listed on a designated sample line, were collected.

 In both types of data collection procedure areas, an enumerator was
 responsible for a small geographic area known as an enumeration district, or
 ED.  An ED usually represented the average workload area for one enumerator.

 In order to reduce the cost of processing the full census sample, a scheme
 was designed, while the sample questionnaires were being processed, to select
 a sample of questionnaires on which the travel time to work, place of work
 and migration data items would be coded (hereafter referred to as POW/MIG
 items).  The sample questionnaires were processed by work units consisting of
 1980 census EDs.  In work units (EDs) where these data items had not yet been
 coded, every second sample questionnaire within the work unit was selected
 for these coding operations.  In work units where the POW/MIG data items
 already had been coded, all sample questionnaires were included in
 tabulations.

 Estimation Procedure For Published Sample Data

 The estimates which appear in census sample publications were obtained from
 an iterative ratio estimation procedure which resulted in the assignment of a
 weight to each sample person or housing unit record.  For any given
 tabulation area, a characteristic total was estimated by summing the weights
 assigned to the persons or housing units in the tabulation area which
 possessed the characteristic.  Estimates of family characteristics were based
 on the weights assigned to the family members designated as householders.
 Each sample person or housing unit record was assigned one weight to be used
 to produce estimates of all characteristics.  (Persons with the migration,
 travel time to work, and place of work characteristic received an additional
 weight.)  For example, if the weight given to a sample person or housing unit
 had the value five, all characteristics of that person or housing unit would
 be tabulated with a weight of five.  The estimation procedure, however, did
 assign weights which vary from person to person or housing unit to housing
 unit.

 The estimation procedure used to assign the weights was performed in
 geographically defined "weighting areas."  Weighting areas were generally
 formed of adjoining portions of geography, which closely agreed with census
 tabulation areas within counties.  Weighting areas were required to have a
 minimum sample of 400 persons.  Weighting areas were never allowed to cross
 state or county boundaries.  In small counties with a sample count of less
 than 400 persons, the minimum required sample condition was relaxed to permit
 the entire county to become a weighting area.

 Within a weighting area, the ratio estimation procedure for persons was
 performed in three states.  For persons the first stage employed seventeen
 household-type groups.  The second stage used two groups:  householders and
 non-householders.  The third stage could potentially use 160 age-sex-race
 -Spanish origin groups.  The stages were as follows:

 Stage I - Type of Household

 Group   Persons in Housing Units with a Family with Own Children under 18.

   1        2 persons in housing unit
   2        3 persons in housing unit
   3        4 persons in housing unit
   4        5 to 7 persons in housing unit
   5        8-or-more persons in housing unit

         Persons in Housing Units with a Family without Own Children under 18.
  6-10      2 persons in housing unit through 8-or-more persons in
              in housing unit

         Persons in All Other Housing Units.

  11        1 person in housing unit
  12-16     2 persons in housing unit through 8-or-more persons in
              in housing unit

  17     Persons in Group Quarters.

 Stage II - Householder/Nonhouseholder

 Group
   1     Householder
   2     Nonhouseholder (including persons in group quarters)

 Stage III - Age/Sex/Race/Spanish Origin

 Group
           White Race
              Persons of Spanish Origin
                 Male
   1                0 to 4 years of age
   2                5 to 14 years of age
   3                15 to 19 years of age
   4                20 to 24 years of age
   5                25 to 34 years of age
   6                35 to 44 years of age
   7                45 to 64 years of age
   8                65 years of age or older
                 Female
  9-16              Same age categories as groups 1 to 8
              Persons Not of Spanish Origin
 17-32           Same age and sex categories as groups 1 to 16

           Black Race
 33-64        Same age/sex/Spanish Origin categories as groups 1 to 32

           Asian, Pacific Islander Race
 65-96        Same age/sex/Spanish Origin categories as groups 1 to 32

           Indian (American) or Eskimo or Aleut Race
 97-128       Same age/sex/Spanish Origin categories as groups 1 to 32

           Other Race (includes those races not listed above)
 129-160      Same age/sex/Spanish Origin categories as groups 1 to 32

 Within a weighting area, the first step in the estimation procedure was to
 assign each sample person record an initial weight.  This weight was
 approximately equal to the inverse of the probability of selecting a person
 for the census sample, for example 6 in a 1-in-6 area.

 The next step in the estimation procedure was to combine, if necessary, the
 groups within each of the three stages prior to the repeated ratio estimation
 in order to increase the reliability of the ratio estimation procedure.  For
 the first and second stages, any group that did not meet certain criteria
 concerning the unweighted sample count or the ratio of the complete count to
 the initially weighted sample count, was combined, or collapsed, with another
 group in the same stage according to a specified collapsing pattern.  At the
 third stage, the "Other" race category was collapsed with the "White" race
 category before the application of the above collapsing criteria as well as
 an additional criterion concerning the number of complete count persons in
 each category.

 As a final step, the initial weights underwent three stages of ratio
 adjustment which used the groups listed above.  At the first stage, the ratio
 of the complete census count to the sum of the initial weights for each
 sample person was computed for each stage I group.  The initial weight
 assigned to each person in a group was then multiplied by the stage I group
 ratio to produce an adjusted weight.  In stage II, the stage I adjusted
 weights were again adjusted by the ratio of the complete census count to the
 sum of the stage I weights for sample persons in each stage II group.
 Finally, the stage II weights were adjusted at stage III by the ratio of the
 complete census count and the sum of the stage II weights for sample persons
 in each stage III group.  The three stages of adjustment were performed twice
 (two iterations) in the order given above.  The weights obtained from the
 second iteration for stage III were assigned to the sample person records.
 However, to avoid complications in rounding for tabulated data, only whole
 number weights were assigned.  For example, if the final weight for the
 persons in a particular group was 7.2, then one-fifth of the sample persons
 in this group were randomly assigned a weight of 8 and the remaining four-
 fifths received a weight of 7.

 Separate weights were derived for tabulating the travel time to work, place
 of work, and migration data items.  The weights were obtained by adjusting
 the weight derived above for persons on questionnaires selected for coding by
 the reciprocal of the ED coding rate and a ratio adjustment to ensure that
 the sum of the weights and the complete-count total population figure would
 agree.

 The ratio estimation procedure for housing units was essentially the same as
 that for persons.  The major difference was that the occupied housing unit
 ratio estimation procedure was done in two stages and the vacant housing unit
 ratio estimation procedure was done in one stage.  The first stage for
 occupied housing units employed sixteen household type categories and the
 second stage could potentially use 190 tenure-race-Spanish origin-value/rent
 groups.  For vacant housing units three groups were utilized.  The stages for
 the ratio estimation for housing units were as follows:

 Occupied housing units

 Stage I - Type of Household

 Group
   1     Housing Units with a Family with Own Children under 18
   2        2 persons in housing unit
   3        3 persons in housing unit
   4        4 persons in housing unit
   5        5 to 7 persons in housing unit
            8-or-more persons in housing unit

         Housing Units with a Family Without Own Children under 18
  6-10      2 persons in housing unit through 8-or-more persons in
              in housing unit

         All Other Housing Units

  11        1 person in housing unit
  12-16     2 persons in housing unit through 8-or-more persons in
              in housing unit

 Stage II - Tenure/Race and Origin of Householder/Value or Rent

         Owner
            White race (Householder)
 Group         Persons of Spanish origin (Householder)
                  Value of house
   1                         $      0 - $  9,999
   2                         $ 10,000 - $ 19,999
   3                         $ 20,000 - $ 24,999
   4                         $ 25,000 - $ 49,999
   5                         $ 50,000 - $ 99,999
   6                         $100,000 - $149,999
   7                         $150,000 +
   8                         Other Owners
               Persons not of Spanish Origin
  9-16            Same value categories as groups 1 to 8

            Black race
  17-32           Same value - Spanish origin categories as groups 1 to 16

            Asian, Pacific Islander Race
  33-48           Same value - Spanish origin categories as groups 1 to 16

            Indian (American) or Eskimo or Aleut Race
  49-64           Same value - Spanish origin categories as groups 1 to 16

            Other Race (includes those races not listed above)
  65-80           Same value - Spanish origin categories as groups 1 to 16

         Renter
            White Race
               Persons of Spanish origin
                  Rent categories
  81                 $  1 - $ 59
  82                 $ 60 - $ 99
  83                 $100 - $149
  84                 $150 - $199
  85                 $200 - $249
  86                 $250 - $299
  87                 $300 - $399
  88                 $400 - $499
  89                 $500 +
  90                 Other Renter
  91                 No Cash Rent
               Persons not of Spanish origin
  92-102          Same rent categories as groups 81 to 91

            Black Race
  103-124         Same rent - Spanish origin categories as groups 81 to 102

            Asian, Pacific Islander Race
  125-146         Same rent - Spanish origin categories as groups 81 to 102

            Indian (American) or Eskimo or Aleut Race
  147-168         Same rent - Spanish origin categories as groups 81 to 102

            Other Race (includes those races not listed above)
  169-190         Same rent - Spanish origin categories as groups 81 to 102

 Vacant housing units

   1        Vacant for Rent
   2        Vacant for Sale
   3        Other Vacant

 The estimates produced by this procedure realize some of the gains in
 sampling efficiency that would have resulted if the population had been
 stratified into the ratio estimation groups before sampling, and the sampling
 rate had been applied independently to each group.  The net effect is a
 reduction in both the standard error and the possible bias of most estimated
 characteristics to levels below what would have resulted from simply using
 the initial (unadjusted) weight.  A by-product of this estimation procedure
 is that the estimates from the sample will, for the most part, be consistent
 with the complete-count figures for the population and housing unit groups
 used in the estimation procedure.

 Selection of the Public-Use-Microdata Samples

 A stratified systematic selection procedure with probability proportional to
 a measure of size was used to select each public-use microdata sample.  The
 sampling elements were the occupied housing unit including all occupants, the
 person in group quarters or the vacant housing unit.  The measure of size was
 the full sample weight that resulted from the 1980 census ratio estimation
 procedure described above.

 It was also necessary to employ a subsampling scheme to yield microdata
 samples with a consistent proportion of cases, from area to area, for which
 place of work, travel time and migration were coded.  The subsampling scheme
 resulted in the occasional designation of selected microdata sample elements
 for which the place of work, travel time and migration information was
 blanked.  This subsampling scheme was instituted so that the POW/MIG data
 would be uniformly available for one-half of all microdata cases, not half in
 most areas but more than half in other areas.  Thus, each 1-percent microdata
 sample gives a 0.5-percent sample of records containing POW/MIG data, and the
 5-percent microdata sample gives a 2.5-percent sample for POW/MIG data.  The
 subsampling scheme was also based on a probability-proportional-to-size
 sampling scheme which utilized measures of size based on both the POW/MIG
 half-sample and full sample weights.

 The sample selection procedures were as follows.  First, the sample units
 were stratified during the selection process.  This stratification was
 intended to improve the reliability of the 5-percent, 1-percent, and 0.1-
 percent samples by defining strata within which there is an appreciable
 degree of homogeneity among the census sample households with respect to
 characteristics of major interest.

 A total of 102 strata were defined:  72 strata for persons living in occupied
 housing units; 24 strata for persons in group quarters (GQ); and 6 strata for
 vacant housing units.  The strata are shown on Figures 6, 7, and 8.

 The sample selection procedures were applied on a state-by-state basis to
 obtain the microdata sample.  Briefly, for any particular state, the
 procedure to accomplish the sample selection consisted of creating a number
 of cells in the computer which correspond to each of the strata defined
 above.  A random value was assigned to each cell and the sample edited detail
 file (i.e., the internal-use microdata from the full census sample) was then
 passed and the appropriate weight from each sample housing unit/GQ person was
 cumulated into the cell corresponding to the appropriate stratum for each
 unit/person.  For occupied housing units, the full sample person weight
 assigned to the householder of the unit was used.  For GQ persons, the full
 sample person weight was used, while for vacant housing units, the full
 sample housing unit weight was used.

 For a given 1-percent sample, when a unit/person caused the cumulation to
 exceed 100, that unit/person was designated for the sample, and the value of
 the cell was reset.  The procedure was then repeated.  For the 5-percent
 sample selection, the procedure was the same except that the cumulation cut-
 off was 20 instead of 100.  The starting value of each cell was set so as to
 minimize the likelihood that any one case would be selected into more than
 one public-use microdata sample, and the overlap among the samples may be
 considered negligible.  There is a small probability that a given individual
 unit (one with a high census weight) may have been selected into the 5-
 percent sample more than once, but this duplication should not have any
 particularly undesirable consequences.

 The POW/MIG subsampling operation was performed by first assigning each
 selected microdata unit, from the POW/MIG coded strata, a measure equal to
 the ratio of the POW/MIG half-sample weight to the full sample weight for the
 selected microdata unit.  These measures were cumulated from the selected
 microdata sample units until the cumulation exceeded 2.  The POW/MIG data for
 the units which caused the cumulation to exceed 2 was retained; otherwise,
 the POW/MIG information was blanked.

 Selection of One-in-One-Thousand and Other Subsamples

 During the sample selection operation, consecutive two-digit subsample
 numbers from 00 to 99 were assigned to each sample case in the five-percent
 and one-percent samples to allow for the designation of various size
 subsamples and as discussed in chapter 3 to allow for the calculation of
 standard errors.  As an example, for a B or C one-percent public-use
 microdata sample, the choice of records having subsample numbers with the
 same "units" digit (e.g., the ones "units" digit includes subsample numbers
 01, 11, 21, ... 91) will provide a one-in-one-thousand subsample.

 The Bureau has chosen one one-in-one thousand subsample from each of the A,
 B, and C public-use microdata samples.  The one-in-one-thousand subsample
 from the A Sample was obtained by selecting those records with a subsample
 number of 13 or 63.  The one-in-one-thousand subsamples from the B and C
 Samples were obtained by selecting those records with subsample number having
 a units digit of 4 on the B Sample, or a units digit of 9 on the C Sample,
 ignoring the tens digit of the two-digit subsample number.

 Samples of any size between 1/20 and 1/10,000 may be selected in a similar
 manner by using appropriate two-digit subsample numbers assigned to the A, B,
 or C microdata samples.  Care must be exercised when selecting such samples.
 If only one "units" digit is required, the "units" digit should be randomly
 selected.  If two "units" digits are required, the first should be randomly
 selected.  If two "units" digits are required, the first should be randomly
 selected and the second should be either five more or five less than the
 first.  Failure to use this procedure, e.g., selection of records with the
 same "tens" digit instead of records with the same "units" digit, would
 provide a one-in-ten subsample but one that would be somewhat more clustered
 and as a result subject to larger sampling error.

RECORD CONTENTS

 General Information

 This chapter, in conjunction with several appendices, defines the record
 layout and applicable codes for the public-use microdata samples.  the
 detailed data dictionary begins on page 55 for the housing record and page 75
 for the person record, with explanatory notes on page 54.

 An index to the basic data items begins below, followed on page 50, by an
 index to allocation items.  Compact lists in numerical sequence of the items
 on the housing and person records appear on pages 52 and 53.  In these
 introductory pages, data fields are specified in the form "H9" or "P12-13,"
 where the letter indicates the Housing or Person record and the numbers
 indicate the character positions occupied on that record.  For example, "P12-
 13" is a two-character field beginning in character 12 of the person record.
 In the data dictionary itself, the "P" or "H" designation appears only at the
 top of the page, and location is expressed in terms of two separate elements,
 the beginning location and the size.

 Index To Items

 Location      Mnemonic      Description

 P31           ENGLISH       Ability to Speak English
 P86           ABLE          Able to Take Job Last Week
 P84           ABSENT        Absent From Work Last Week
 H40           ACCESS        Access
 H60           ACREAGE1      Acreage of Property (H10a on questionnaire)
 H61           ACREAGE2      Acreage of Property (H15a on questionnaire)
 P44           COLL75        Activity Status in 1975:  Attending College
 P43           AF75          Activity Status in 1975:  In Armed Forces
 P45           WORK75        Activity Status in 1975:  Working at a job or
                                Business
 P8-9          AGE           Age
 P10           QTRBIRTH      Age:  Quarter of Birth
 P35-36        AGEMAR        Age at First Marriage
 P37           QTRMAR        Age at First Marriage:  Quarter
 H41           YRBUILT       Age of Structure
 H28           GQTYPE        Aged, Inmate of Home for
 H51           AIRCOND       Air Conditioning
 H117-H162                   Allocation Flags for Housing Items (For detail,
                                see page 50.)
 P140-P193                   Allocation Flags for Population Items (For
                                detail, see page 50.)
 P16-18        ANCSTRY1      Ancestry--1st entry
 P19-21        ANCSTRY2      Ancestry--2nd entry
 H36-37        UNITS1        Apartments
 H9            AREATYPE      Area, Type of
 P81           LABOR         Armed Forces Status
 P43           AF75          Armed Forces Status in 1975
 H56           AUTOS         Automobiles Available
 H48           BATHROOM      Bathrooms
 H45           BEDROOMS      Bedrooms
 P22-24        BIRTHPL       Birth, Place of
 H32           VACANCY3      Boarded Up Status
 P106-110      INCOME2       Business Income in 1979
 P87-89        INDUSTRY      Business, Type of (Industry)
 P68           RIDERS        Carpool Occupancy
 P67           CARPOOL       Carpooling
 H9            AREATYPE      Central City Residence
 P61           POWCC         Central City Recode:  Place of Work
                               (C Sample only
 P2-3          RELAT1        Children
 H105          CHILDREN      Children, Own, Presence and Age of
 P32-33        FERTILITY     Children Ever Born
 P25           CITIZEN       Citizenship
 P93           CLASS         Class of Worker
 P39, 40-41    SCHOOL        College Attendance
 P44           COLL75        College Attendance in 1975
 H28           GQTYPE        College Dormitory, Person in
 H63           COMMUSE       Commercial Establishment or Medical Office on
                               Property
 P65-66        MEANS         Commuting to Work
 H35           CONDO         Condominium Status
 H99-100       RENT1         Contract Rent
 H55           FUELCOOK      Cooking Fuel
 H28           GQTYPE        Correctional Institution, Inmate of
 P22-24        BIRTHPL       Country of Birth
 H6-8          COGRP         County Group (A and B Samples only)
 P57-59        POWCOGRP      County Group:  Place of Work (A and B Samples)
 P49-51        COGRP75       County Group:  Residence in 1975
                               (A and B Samples)
 P52           MIG75         County-State Recode:  Residence in 1975
 P4            RELAT2        Detailed Relationship
 P69           DISABIL1      Disability Which Limits Work
 P71           DISABIL3      Disability Which Limits or Prevents Use of
                               Public Transportation
 P70           DISABIL2      Disability Which Prevents Work
 P116-120      INCOME4       Dividend, Interest, or Net Rental Income in 1979
 H3            DIVISION      Division
 H33           VACANCY4      Duration of Vacancy
 P111-115      INCOME3       Earnings in 1979:  From Farm Self-Employment
 P106-110      INCOME2       Earnings in 1979:  From Nonfarm Self-Employment
 P101-105      INCOME1       Earnings in 1979:  From Wage or Salary
 P42           FINGRADE      Education:  Finished Highest Grade
 P40-41        GRADE         Education:  Highest Year of School Attended
 P39           SCHOOL        Education:  School Enrollment and Type of School
 H67-69        ELECCOST      Electricity, Monthly Cost of
 H66           ELECPAID      Electricity, Payment of
 H43           ELEVATOR      Elevator, Passenger
                             Employment in 1979 - See Work in 1979
 P81           LABOR         Employment Status
 P31           ENGLISH       English, Ability to Speak
 H112-116      FAMINCOM      Family Income in 1979
 P2-3          RELAT1        Family Membership
 H104          HHTYPE        Family Type
 P111-115      INCOME3       Farm Self-Employment Income in 1979
 H62           FARM          Farm Status and Sales of Farm Products
                             Farm Workers - See:  Occupation
 P32-33        FERTILITY     Fertility:  Children Ever Born
 P42           FINGRADE      Finished Highest Grade
 P22-24        BIRTHPL       Foreign Country of Birth
 H55           FUELCOOK      Fuel, Cooking
 H53           FUELHEAT      Fuel, House Heating
 H54           FUELWTR       Fuel, Water Heating
 P82-83        HOURS         Full Time-Part Time Work:  Hours Worked Last Week
 P79-98        HOURS79       Full Time-Part Time Work in 1979:  Usual Hours
                               Worked Per Week
 H71-73        GASCOST       Gas, Monthly Cost of
 H70           GASPAID       Gas, Payment of
                             Government Workers - See:  Class of Worker
 H101-103      RENT2         Gross Rent
 P2-3          RELAT1        Group Quarters Status
 H28           GQTYPE        Group Quarters, Type of
 H52           HEATING       Heating Equipment
 P40-41        GRADE         Highest Year of School Attended
 H29           TENURE        Home Ownership
 P82-83        HOURS         Hours Worked Last Week
 P97-98        HOURS79       Hours Worked Per Week in 1979, Usual
 H53           FUELHEAT      House Heating Fuel
 H107-111      HHINCOME      Household Income in 1979
 P2-3          RELAT1        Household Relationship
 P4            RELAT2        Household Relationship, Detailed
 H26-27        PERSONS       Household Size
 H104          HHTYPE        Household Type
 H20-25        SERIALNO      Housing Unit/GQ Person Serial Number
 P26           IMMIGR        Immigration, Year of
 H94           INSINCL       Inclusion of Insurance Premiums in Payment to
                               Lender
 H93           TAXINCL       Inclusion of Real Estate Taxes in Payment to
                               Lender
 P134-138      INCOME8       Income From All Sources in 1979
 P129-133      INCOME7       Income in 1979:  All Other
 H112-116      FAMINCOM      Income in 1979:  Family
 P111-115      INCOME3       Income in 1979:  Farm Self-Employment
 H107-111      HHINCOME      Income in 1979:  Household
 P116-120      INCOME4       Income in 1979:  Interest, Dividend and Net
                               Rental
 P106-110      NSUBFAM       Income in 1979:  Nonfarm Self-Employment
 P125-128      INCOME6       Income in 1979:  Public Assistance
 P121-124      INCOME5       Income in 1979:  Social Security
 P101-105      INCOME1       Income in 1979:  Wage or Salary
 P139          POVERTY       Income Ratio to Poverty Level
 P87-89        INDUSTRY      Industry
 P2-3, H28     RELAT1        Inmate Status
 H28           GQTYPE        Institution, Type of
 H83-86        TAXINSUR      Insurance Premiums and Real Estate Taxes
                               Combined
 H94           INSINCL       Insurance Premiums, Inclusion in Payment to
                               Lender
 P116-120      INCOME4       Interest, Dividend, and Net Rental Income in 1979
 H47           KITCHEN       Kitchen Facilities
 P81           LABOR         Labor Force Status
 P27           LANG1         Language Usage
 P28-30        LANG2         Language Spoken at Home
 P31           ENGLISH       Language:  Ability to Speak English
 P85           LOOKING       Looking for Work
 P35-36        AGEMAR        Marital History:  Age at First Marriage
 P37           QTRMAR        Marital History:  Quarter of First Marriage
 P34           TIMESMAR      Marital History:  Times Married
 P38           WIDOWED       Marital History:  Widowed
 P11           MARITAL       Marital Status
 H104          HHTYPE        Married-Couple Families
 P65-66        MEANS         Means of Transportation to Work
 H28           GQTYPE        Mental Hospital, Inmate of
 H9            AREATYPE      Metropolitan Residence (A and B Samples)
                             Migration - See:  Residence in 1975; Year
                               Householder Moved Into Unit
 P46           MIGWGT        Migration/Place of Work/Travel Time Weight
                             Military - See Labor Force Status;
                               Armed Forces Status in 1975; Veteran Status;
                               Period of Service
 H28           GQTYPE        Military Quarters
 H36-37        UNITS1        Mobile Homes
 H67-69        ELECCOST      Monthly Cost of Electricity
 H71-73        GASCOST       Monthly Cost of Gas
 H87           MORTGAG1      Mortgage Status
 H88           MORTGAG2      Mortgage:  Second or Junior
 H89-92        MORTGAG3      Mortgage:  Total Monthly Payment to Lender
 P25           CITIZEN       Nativity
 P106-110      INCOME2       Nonfarm Self-Employment Income in 1979
 H26-27        PERSONS       Number of Person Records Following This Housing
                               Unit Record
 H106          NSUBFAM       Number of Subfamilies in Family
 P90-92        OCCUP         Occupation
 H78           FUELPAID      Oil, Coal, Kerosene, Wood, etc., Payment of
 H79-82        FUELCOST      Oil, Coal, Kerosene, Wood, etc., Yearly Cost of
 H105          CHILDREN      Own Children, Presence and Age of
 H95-98        OWNERCST      Owner Costs, Selected Monthly
 H29           TENURE        Owner/Renter Status
 H43           ELEVATOR      Passenger Elevator
 H66           ELECPAID      Payment of Electricity
 H70           GASPAID       Payment of Gas
 H78           FUELPAID      Payment of Oil, Coal, Kerosene, Wood, etc.
 H74           WTRPAID       Payment of Water
 P75           VETERAN4      Period of Service Between February 1955 and
                               July 1964
 P79           VETERAN8      Period of Service During Any Other Time
 P76           VETERAN5      Period of Service During Korean Conflict
                               (June 1950-January 1955)
 P74           VETERAN3      Period of Service During Vietnam Era
                               (August 1964-April 1975)
 P78           VETERAN7      Period of Service During World War I
                               (April 1917-November 1918)
 P77           VETERAN6      Period of Service During World War II
                               (September 1940-July 1947)
 P73           VETERAN2      Period of Service May 1975 or later
 H26-27        PERSONS       Persons in Household
 P22-24        BIRTHPL       Place of Birth
 P46           MIGWGT        Place of Work/Migration/Travel Time Weight
 P61           POWCC         Place of Work:  Central City Recode (C
                               Sample only)
 P57-59        POWCOGRP      Place of Work:  County Group (A and B Samples)
 P62           POWPLSIZ      Place of Work:  Place Size (C Sample only)
 P60           POWMETRO      Place of Work:  SMSA Recode (A and B Samples)
 P55-56        POWSTATE      Place of Work:  State
 P62           POWPLSIZ      Place Size:  Place of Work (C Sample only)
 H46           PLUMBING      Plumbing Facilities
 P139          POVERTY       Poverty Status in 1979
 H105          CHILDREN      Presence and Age of Own Children
 P68           RIDERS        Private Vehicle Occupancy
 P125-128      INCOME6       Public Assistance Income in 1979
 P71           DISABIL3      Public Transportation Disability Status
 P65-66        MEANS         Public Transportation to Work
 P10           QTRBIRTH      Quarter of Birth
 P37           QTRMAR        Quarter of First Marriage
 P12-13        RACE          Race
 H18-H19       SUBSAMPL      Random Group Subsample Number
 P139          POVERTY       Ratio of Family or Unrelated Individual Income
                               to Poverty Cutoff in 1979
 H83-86        TAXINSUR      Real Estate Taxes and Insurance Premiums Combined
 H93           TAXINCL       Real Estate Taxes:  Inclusion in Payment to
                               Lender
 H1/P1         RECTYPE       Record Type
 H3            DIVISION      Region/Division
 P2-3          RELAT1        Relationship
 P4            RELAT2        Relationship, Detailed
 H99-100       RENT1         Rent, Contract
 H101-103      RENT2         Rent, Gross
 P116-120      INCOME4       Rental, Net, Dividend, and Interest Income
                               in 1979
 H29           TENURE        Renter/Owner Status
 P49-51        COGRP75       Residence in 1975:  County Group
                               (A and B Samples)
 P53-54        METRO75       Residence in 1975:  SMSA Recode
                               (A and B Samples)
 P47-48        STATE75       Residence in 1975:  State
 P52           MIG75         Residence in 1975:  State-County Recode
 H28           GQTYPE        Rooming House, Person in
 H44           ROOMS         Rooms
 H9            AREATYPE      Rural Residence (C Sample only)
 H62           FARM          Sales of Farm Products
 H2            SAMPLE        Sample Identifier
 P39           SCHOOL        School Enrollment and Type of School
 P42           FINGRADE      School:  Finished Highest Grade
 P40-41        GRADE         School:  Highest Year Attended
 H30           VACANCY1      Seasonal and Migratory Vacancy Status
 H88           MORTGAG2      Second or Junior Mortgage
 H95-98        OWNERCST      Selected Monthly Owner Costs
                             Self-Employed Workers - See:  Class of Worker
                             Self-Employed Earnings - See:  Income in 1979
 H20-25        SERIALNO      Serial Number for Housing Unit/GQ Person
 H50           SEWAGE        Sewage Disposal
 P7            SEX           Sex
 H26-27        PERSONS       Size of Household
 H10-13        SMSA          SMSA (A and B Samples only)
 P53-54        METRO75       SMSA Recode:  Residence in 1975 (A and B Samples)
 P60           POWMETRO      SMSA Recode:  Place of Work (A and B Samples)
 P121-124      INCOME5       Social Security Income in 1979
 H49           WATER         Source of Water
 P14           SPANISH       Spanish Origin
 P15           SURNAME       Spanish Surname
 P22-24        BIRTHPL       State of Birth
 P52           MIG75         State-County Recode:  Residence in 1975
 H4-5          STATE         State
 P55-56        FUELCOOK      State:  Place of Work
 P47-48        KITCHEN       State:  Residence in 1975
 H42           STORIES       Stories in Structure
 H106          NSUBFAM       Subfamilies in Family, Number of
 P6            SUBFAM2       Subfamily Number
 P5            SUBFAM1       Subfamily Relationship
 H18-19        SUBSAMPL      Subsample Number
 H83-86        TAXINSUR      Taxes, Real Estate and Insurance Premiums
                               Combined
 H58           TELEPHON      Telephone in Housing Unit
 H29           TENURE        Tenure
 P34           TIMESMAR      Times Married
 H89-92        MORTGAG3      Total Monthly Payment to Lender
 P65-66        MEANS         Transportation to Work, Means of
 P63-64        TIME          Travel Time to Work
 P46           MIGQGT        Travel Time/Place of Work/Migration Weight
 H57           TRUCKS        Trucks and Vans Available
 H9            AREATYPE      Type of Area
 H28           GQTYPE        Type of Group Quarters
 P39           SCHOOL        Type of School
 P81           LABOR         Unemployment
 P99-100       WEEKSU79      Unemployment in 1979:  Weeks Unemployed
 P86           ABLE          Unemployment:  Able to Take Job Last Week
 P84           ABSENT        Unemployment:  Absent From Work Last Week
 P85           LOOKING       Unemployment:  Looking for Work
 H38-39        UNITS2        Units at Address
 H36-37        UNITS1        Units in Structure
 H9            AREATYPE      Urban/Rural Status (C Sample Only)
 H14-17        UA            Urbanized Area (C Sample Only)
 H34           UHE           Usual Home Elsewhere
 P97-98        HOURS79       Usual Hours Worked Per Week in 1979
 H33           VACANCY4      Vacancy, Duration of
 H32           VACANCY3      Vacancy Status, Boarded Up
 H30           VACANCY1      Vacancy Status, Seasonal and Migratory
 H31           VACANCY2      Vacancy Type
 H64-65        VALUE         Value
 H57           TRUCKS        Vans and Trucks Available
 P68           RIDERS        Vehicle Occupancy:  Carpool
 H56           AUTOS         Vehicles Available:  Automobiles
 H57           TRUCKS        Vehicles Available:  Trucks and Vans
 P72           VETERAN1      Veteran Status
 P75           VETERAN4      Veteran's Period of Service:  Between
                               February 1955 and July 1964
 P79           VETERAN8      Veteran's Period of Service:  During Any Other
                               Time
 P76           VETERAN5      Veteran's Period of Service:  During Korean
                               Conflict (June 1950-January 1955)
 P74           VETERAN3      Veteran's Period of Service:  During Vietnam Era
                               (August 1964-April 1975)
 P78           VETERAN7      Veteran's Period of Service:  During World War I
                               (April 1917-November 1918)
                             Wage and Salary Workers - See Class of Worker
 P101-105      INCOME1       Wage and Salary Income in 1979
 H54           FUELWTR       Water Heating Fuel
 H74           WTRPAID       Water, Payment of
 H49           WATER         Water, Source of
 P99-100       WEEKSU79      Weeks Unemployed in 1979
 P95-96        WEEKSW79      Weeks Worked in 1979
 P125-128      INCOME6       Welfare Income in 1979
 P11           MARITAL       Widowed (Current Status)
 P38           WIDOWED       Widowed (from First Marriage)
 P69           DISABIL1      Work Disability Status:  Limited
 P70           DISABIL2      Work Disability Status:  Prevented from Working
                             Work in 1979 - See:  Work Last Year, Weeks Worked
                               in 1979, Usual Hours Worked Per Week in 1979
 P94           WORK79        Work Last Year
 P45           WORK75        Work Status in 1975
 H59           YRMOVED       Year Householder Moved into Unit
 P80           YEARWORK      Year Last Worked
 P26           IMMIGR        Year of Immigration
 P40-41        GRADE         Year of School, Highest Attended
 H41           YRBUILT       Year Structure Built
 H79-82        FUELCOST      Yearly Cost of Oil, Coal, Kerosene, Wood, Etc.

                             Allocation of:

 P155          ALANG3        Ability to Speak English
 H126          AACCESS       Access
 H146          AACRE1        Acreage of Poverty (H10a on questionnaire)
 H147          AACRE2        Acreage of Poverty (H15a on questionnaire)
 P164          ACOLL75       Activity in 1975:  Attending College
 P163          AAF75         Activity in 1975:  In Armed Forces
 P165          AWORK75       Activity in 1975:  Working at a Job or Business
 P143          AAGE          Age
 P158          AAGEMR        Age at First Marriage and Quarter of First
                               Marriage
 H137          AAIRCOND      Air Conditioning
 P193          AINCOME7      All Other Income in 1979
 H142          AAUTOS        Automobiles Available
 H134          ABATHROO      Bathrooms
 H131          ABEDROOM      Bedrooms
 H121          AVAC3         Boarded Up Status
 P171          ARIDERS       Carpool Occupancy
 P170          ACARPOOL      Carpooling
 P156          AFERTIL       Children Ever Born
 P151          ACITIZEN      Citizenship
 P182          ACLASS        Class of Worker
 H149          ACOMMERC      Commercial Establishment or Medical Office
 H123          ACONDO        Condominium Status
 H162          ARENT1        Contract Rent
 H141          AFUELCOO      Cooking Fuel
 P141          ARELAT2       Detailed Relationship
 H122          AVAC4         Duration of Vacancy
 P189          AINCOME3      Farm Self-Employment Income in 1979
 H148          AFARM         Farm Status and Sales of Farm Products
 P162          AFINGRAD      Finished Grade
 H138          AHEATING      Heating Equipment
 P161          AYEARSCH      Highest Year of School Attended
 P179          AHOURS        Hours Worked Last Week
 H139          AFUELHEA      House Heating Fuel
 P140          ARELAT1       Household Relationship
 H161          AINSINCL      Inclusion of Insurance Premiums in Payment to
                               Lender
 H160          ATAXINCL      Inclusion of Taxes in Payment to Lender
 P180          AINDUSTR      Industry
 P190          AINCOME4      Interest, Dividend or Net Rental Income in 1979
 H133          AKITCHEN      Kitchen Facilities
 P178          ALABOR        Labor Force Status
 P153          ALANG1        Language Usage
 P154          ALANG2        Language Spoken at Home
 P145          AMARITAL      Marital Status
 P169          AMEANS        Means of Transportation to Work
 H151          AELECCOS      Monthly Cost of Electricity
 H152          AGASCOST      Monthly Cost of Gas
 H157          AMORTG1       Mortgage Status
 P188          AOCCUP        Occupation
 H129          AELEVATO      Passenger Elevator
 P150          ABIRTHPL      Place of Birth
 H132          APLUMBIN      Plumbing Facilities
 P149          AANCSTRY      Pre-edit of Ancestry (both 1st and 2nd entry)
 P147          ARACE2        Pre-edit of Detailed Race and American Indian
 P192          AINCOME6      Public Assistance Income in 1979
 P174          DISABL3       Public Transportation Disability Status
 P144          AQTRBRTH      Quarter of Birth
 P146          ARACE1        Race
 H155          ATAX          Real Estate Taxes
 P166          AMIG751       Residence in 1975:  Same House/Different House
 P167          AMIG752       Residence in 1975:  Specific Area
 H130          AROOMS        Rooms
 P160          ASCHOOL       School Enrollment and Type of School
 H119          AVAC1         Seasonal and Migratory Vacancy Status
 H158          AMORTG2       Second or Junior Mortgage
 H136          ASEWAGE       Sewage Disposal
 P142          ASEX          Sex
 P191          AINCOME5      Social Security Income in 1979
 H135          AWATER        Source of Water
 P148          ASPANISH      Spanish Origin
 H128          ASTORIES      Stories in Structure
 H144          ATELEPHO      Telephone in Housing Unit
 H118          ATENURE       Tenure
 P157          ATIMESMA      Times Married
 H159          AMORTG3       Total Monthly Payment to Lender
 P168          ATIME         Travel Time to Work
 H143          ATRUCKS       Trucks and Vans Available
 H117          AGQTYPE       Type of Group Quarters
 H125          AUNITS2       Units at Address
 H124          AUNITS1       Units in Structure
 P185          AHOUR79       Usual Hours Worked per Week in 1979
 H120          AVAC2         Vacancy Type
 H150          AVALUE        Value
 P175          AVET1         Veteran Status
 P176          AVET2         Veteran's Period of Service
 P187          AINCOME1      Wage or Salary Income in 1979
 H140          AFUELWTR      Water Heating Fuel
 P186          AWEEKU79      Weeks Unemployed in 1979
 P184          AWEEKW79      Weeks Worked in 1979
 P159          AWIDOWED      Widowed
 P172          ADISABL1      Work Disability Status:  Limited
 P173          ADISABL2      Work Disability Status:  Prevented from Working
 P183          AWORK79       Work Last Year
 H145          AYRMOVED      Year Householder Moved Into Unit
 P177          AYEARWRK      Year Last Worked
 P152          AIMMIGR       Year of Immigration
 H127          AYRBUILT      Year Structure Built
 H154          AFUELCOS      Yearly Cost of Oil, Coal, Kerosene, Wood, etc.
 H153          AWTRCOST      Yearly Cost of Water
 H156          AINSUR        Yearly Insurance Premium

 Items On Housing Record

 Character
 Location      Description

 H1            Record Type (Housing Record)
 H2            Sample Identifier
 H3            Region/Division
 H4-5          State
 H6-8          County Group (A and B Samples only)
 H9            Type of Area
 H10-13        SMSA (A and B Samples only)
 H14-17        Urbanized Area (C Sample only)
 H18-19        Subsample Number
 H20-25        Housing Unit/CQ Person Serial Number
 H26-27        Number of Person Records Following This Housing Unit Record
 H28           Type of Group Quarters
 H29           Tenure
 H30           Seasonal and Migratory Vacancy Status
 H31           Vacancy Type
 H32           Boarded Up Status
 H33           Duration of Vacancy
 H34           Usual Home Elsewhere
 H35           Condominium Status
 H36-37        Units in Structure
 H38-39        Units at Address
 H40           Access
 H41           Year Structure Built
 H42           Stories in Structure
 H43           Passenger Elevator
 H44           Rooms
 H45           Bedrooms
 H46           Plumbing Facilities
 H47           Kitchen Facilities
 H48           Bathrooms
 H49           Source of Water
 H50           Sewage Disposal
 H51           Air Conditioning
 H52           Heating Equipment
 H53           Fuels
 H54           Water Heating Fuel
 H55           Cooking Fuel
 H56           Automobiles Available
 H57           Trucks and Vans Available
 H58           Telephone in Housing Unit
 H59           Year Householder Moved into Unit
 H60           Acreage of Property (H10a on questionnaire)
 H61           Acreage of Property (H15a on questionnaire)
 H62           Farm Status and Sales of Farm Products
 H63           Commercial Establishment or Medical Office on Property
 H64-65        Value
 H66           Payment of Electricity
 H67-69        Monthly Cost of Electricity
 H70           Payment of Gas
 H71-73        Monthly Cost of Gas
 H74           Payment of Water
 H75-77        Yearly Cost of Water
 H78           Payment of Oil, Coal, Kerosene, Wood, Etc.
 H79-82        Yearly Cost of Oil, Coal, Kerosene, Wood, Etc.
 H83-86        Real Estate Taxes Last Year and Yearly Insurance Premiums
                 Combined
 H87           Mortgage Status
 H88           Second or Junior Mortgage
 H89-92        Total Monthly Payment to Lender
 H93           Inclusion of Real Estate Taxes in Payment to Lender
 H94           Inclusion of Insurance Premiums in Payment to Lender
 P95-98        Selected Monthly Owner Costs
 H99-100       Contract Rent
 H101-103      Gross Rent
 H104          Household Type
 H105          Presence and Age of Own Children
 H106          Number of Subfamilies in Family
 H107-111      Household Income in 1979
 H112-116      Family Income in 1979
 H117 to       Allocation Flags for Housing Items
   H162
 H163-193      Filler (zeroes)

 Items On Person Record

 Character
 Location      Description

 P1            Record Type (Person Record)
 P2-3          Relationship
 P4            Detailed Relationship
 P5            Subfamily Relationship
 P6            Subfamily Number
 P7            Sex
 P8-9          Age
 P10           Quarter of Birth
 P11           Marital Status
 P12-13        Race
 P14           Spanish Origin
 P15           Spanish Surname
 P16-18        Ancestry--1st entry
 P19-21        Ancestry--2nd entry
 P22-24        Place of Birth
 P25           Citizenship
 P26           Year of Immigration
 P27           Language Spoken at Home Other Than English
 P28-30        Language Spoken at Home
 P31           Ability to Speak English
 P32-33        Children Ever Born
 P34           Times Married
 P35-36        Age at First Marriage
 P37           Quarter of First Marriage
 P38           Widowed
 P39           School Enrollment and Type of School
 P40-41        Highest Year of School Attended
 P42           Finished Highest Grade
 P43           Activity in 1975:  In Armed Forces
 P44           Activity in 1975:  Attending College
 P45           Activity in 1975:  Working
 P46           Migration/Place of Work/Travel Time Weight
 P47-48        Residence in 1975
 P49-51        Residence in 1975:  County Group
 P52           Residence in 1975:  State-County Recode
 P53-54        Residence in 1975:  SMSA Recode
 P55-56        Place of Work:  State
 P57-59        Place of Work:  County Group (A and B Sample)
 P60           Place of Work:  SMSA Recode (A and B Sample)
 P61           Place of Work:  Central City Recode (C Sample only)
 P62           Place of Work:  Place Size
 P63-64        Travel Time to Work
 P65-66        Means of Transportation to Work
 P67           Carpooling
 P68           Carpool Occupancy
 P69           Work Disability Status
 P71           Public Transportation Disability Status
 P72           Veteran Status
 P73           Period of Service May 1975 or later
 P74           Period of Service During Vietnam Era
 P75           Period of Service Between
 P76           Period of Service During Korean Conflict
 P77           Period of Service During World War II
 P78           Period of Service During World War I
 P79           Period of Service During Any Other Time
 P80           Year Last Worked
 P81           Labor Force Status
 P82-83        Hours Worked Last Week
 P84           Absent From Work Last Week
 P85           Looking for Work
 P86           Able to Take Job Last Week
 P87-89        Industry
 P90-92        Occupation
 P93           Class of Worker
 P94           Work Last year
 P95-96        Weeks Worked in 1979
 P97-98        Usual Hours Worked Per Week in 1979
 P99-100       Weeks Unemployed in 1979
 P101-105      Wage or Salary Income in 1979
 P106-110      Nonfarm Self-Employment Income in 1979
 P111-115      Farm Self-Employment Income in 1979
 P116-120      Interest, Dividend, or Net Rental Income in 1979
 P121-124      Social Security Income in 1979
 P125-128      Public Assistance Income in 1979
 P129-133      All Other Income in 1979
 P134-138      Income From All Sources in 1979
 P139          Poverty Status in 1979
 P140 to       Allocation Flags for Population
   P193          Items
 How To Use The Data Dictionary

 The following computer-generated pages document the data contents and record
 layout of the file.  Below is a brief description of the information provided
 for each data item.

 The first line of each data item descriptive gives the name, size/scale,
 begin position, and item title.  On subsequent lines are value codes and any
 applicable notes.  Each of these elements is defined below.

     1.  Name.  This is an arbitrarily assigned 8-character mnemonic
         identifier, e.g., "STATE," "INCOME8."

     2.  Size/Scale.  The size is the number of characters occupied by the
         item.  The reference to scale is not applicable since none of the
         data are scaled.

     3.  Begin.  This is the location within the 193-character data record of
         the first character of the data item.

     4.  Description.  (Not labeled on the data dictionary.)

         Title.  This is a single 40-character line or a set of 40-character
         lines which provide the title for the data item.

         Value Codes and Notes.  Lines after the title describe individual
         categories of the data item.  Each code for which a separate label is
         provided is listed at the left.  Codes for which the values are self-
         explanatory (e.g., dollar amounts in an income field), are not listed
         individually, but are defined in a range listed in the right-hand
         column.

 The file used to generate the following printout is available as part of any
 CENSPAC tape sold after February 1983, or in conjunction with the County
 Group Equivalency File.
PUMSH Data Dictionary

 Record H
  Positions 1-20
                  SIZE/
 NAME             SCALE   BEGIN

 RECTYPE            1         1
                           Record Type
           H               Housing Record

 SAMPLE             1         2
                           Sample Identifier
           1               A Sample
           2               B Sample
           3               C Sample

 DIVISION           1         3
                           Region/Division
           0               Region/division not identifiable (selected SMSA's
                             on B Sample, See App. C)
                           Northeast region:
           1                 New England division
           2                 Middle Atlantic division
                           North Central region:
           3                 East North Central division
           4                 West North Central division
                           South region:
           5                 South Atlantic division
           6                 East South Central division
           7                 West South Central division
                           West region:
           8                 Mountain division
           9                 Pacific division

 STATE              2         4
                           State
         01-56             FIPS state code (See App. A)
         61-68             State group code (selected states on C Sample-
                             See App. A)
          99               State not identified (selected county groups on
                             B Sample-See App. C)

 COGRP              3         6
                           County Group (A and B Samples only)
         000               N/A (C Sample)
       001-998             County group code (unique within state)

 AREATYPE           1         9
                           Type of Area
           1               Central city of SMSA (selected central cities on
                             A and B Samples)
           2               SMSA, outside central city (selected areas on
                             A and B Samples)
           3               SMSA, central city/remainder not separately
                             identified (selected SMSAs or SMSA parts on
                             A and B Samples for which codes 1 and 2 cannot
                             be shown)
           4               Mixed SMSA/non SMSA area (A Sample only)
           5               Outside SMSAs (A and B Samples)
           6               Central city of urbanized area (C Sample only)
           7               Urban fringe (C Sample only)
           8               Urban, outside urbanized areas (C Sample only)
           9               Rural (C Sample only)

 SMSA               4        10
                           SMSA (A and B Samples only)
         0000              N/A (C Sample, area outside SMSAs)
      0040-9340            FIPS SMSA code, selected SMSAs (See app. B)
         9999              County group consisting of 2 or more SMSAs or mixed
                             SMSA/nonSMSA area)

 UA                 4        14
                           Urbanized Area (C Sample only)
         0000              N/A (A and B Samples, area outside identified UAs)
      0080-9320            Census urbanized area code (selected UAs-See
                             App. D)

 SUBSAMPL           2        18
                           Subsample Number
        00-99              See text, pp. 29 and 43

 SERIALNO           6        20
                           Housing Unit/GQ Person Serial Number
    000000-999999          Unique identifier assigned within State or
                             State group
 Positions 26-40

 PERSONS            2        26
                           Number of Person Records Following This Housing
                             Unit Record
          00               Vacant Unit
          01               One person record (one person in household or any
                             person in group quarters)
        02-31              Number of persons in household

 GQTYPE             1        28
                           Type of Group Quarters
           0               N/A (not in group quarters)
           1               Inmate of mental hospital
           2               Inmate of home for the aged
           3               Inmate of correctional institution
           4               Inmate of other institution
           5               In military quarters
           6               In college dormitory
           7               In rooming house
           8               Other in group quarters, including noninmate living
                             in institution

 TENURE             1        29
                           Tenure
           0               N/A (vacant unit or group quarters)
           1               Owner occupied
                           Renter occupied:
           2                 With cash rent
           3                 No cash rent

 VACANCY1           1        30
                           Seasonal and Migratory Vacancy Status
           0               N/A (occupied or group quarters)
           1               Vacant, year round
           2               Vacant, seasonal or migratory

 VACANCY2           1        31
                           Vacancy Type
           0               N/A (occupied, group quarters or vacant seasonal
                             or migratory)
           1               For rent
           2               For sale only
           3               Rented or sold, awaiting occupancy
           4               Held for occasional use
           5               Other vacant

 VACANCY3           1        32
                           Boarded Up Status
           0               N/A (occupied, group quarters or vacant seasonal
                             or migratory)
           1               Boarded up
           2               Not boarded up

 VACANCY4           1        33
                           Duration of Vacancy
           0               N/A (occupied, group quarters or vacant seasonal
                             or migratory)
           1               Less than 1 month
           2               1 up to 2 months
           3               2 up to 6 months
           4               6 up to 12 months
           5               1 year up to 2 years
           6               2 years or more

 UHE                1        34
                           Usual Home Elsewhere
           0               Not originally reported as usual home elsewhere, or
                             elsewhere, or group quarters
           1               Originally reported as usual home elsewhere

 CONDO              1        35
                           Condominium Status
           0               N/A (group quarters)
           1               Not a condominium unit
           2               Condominium unit

 UNITS1             2        36
                           Units in Structure
           00              N/A (group quarters)
           01              Mobile home or trailer
           02              One-family house detached from any other house
           03              One-family house attached to one or more houses
           04              Building for 2 families
           05              Building for 3 or 4 families
           06              Building for 5 to 9 families
           07              Building for 10 to 19 families
           08              Building for 20 to 49 families
           09              Building for 50 or more families
           10              Boat, tent, van, etc.

 UNITS2             2        38
                           Units at Address
           00              N/A (group quarters)
           01              One
           02              Two
           03              Three
           04              Four
           05              Five
           06              Six
           07              Seven
           08              Eight
           09              Nine
           10              Ten or more
           11              Mobile home or trailer

 ACCESS             1        40
                           Access
           0               N/A (group quarters)
           1               Access to unit directly from the outside
                             or through a common or public hall
           2               Access to unit through someone else's living
                             quarters
 Positions 41-60

 YRBUILT            1        41
                           Year Structure Built
           0               N/A (group quarters)
           1               1979 to March 1980
           2               1975 to 1978
           3               1970 to 1974
           4               1960 to 1969
           5               1950 to 1959
           6               1940 to 1949
           7               1939 or earlier

 STORIES            1        42
                           Stories in Structure
           0               N/A (group quarters)
           1               1 to 3 stories
           2               4 to 6 stories
           3               7 to 12 stories
           4               13 or more stories

 ELEVATOR           1        43
                           Passenger Elevator
           0               N/A (group quarters or structure with less than
                             4 stories)
           1               With passenger elevator in structure
           2               No passenger elevator in structure

 ROOMS              1        44
                           Rooms
           0               N/A (group quarters)
           1               One room
           2               Two rooms
           3               Three rooms
           4               Four rooms
           5               Five rooms
           6               Six rooms
           7               Seven rooms
           8               Eight rooms
           9               Nine or more rooms

 BEDROOMS           1        45
                           Rooms
           0               N/A (group quarters)
           1               None
           2               One bedroom
           3               Two bedrooms
           4               Three bedrooms
           5               Four bedrooms
           6               Five or more bedrooms

 PLUMBING           1        46
                           Plumbing Facilities
           0               N/A (group quarters)
           1               Complete plumbing for exclusive use
                           Lacking complete plumbing for exclusive use:
           2                 Complete plumbing but used by another household
           3                 Some but not all plumbing facilities
           4               No plumbing facilities

 KITCHEN            1        47
                           Kitchen Facilities
           0               N/A (group quarters)
           1               Complete kitchen facilities
           2               No complete kitchen facilities

 BATHROOM           1        48
                           Bathrooms
           0               N/A (group quarters)
           1               No bathroom or only a half bath
           2               One complete bathroom
           3               One complete bathroom plus half bath(s)
           4               Two or more complete bathrooms

 WATER              1        49
                           Source of Water
           0               N/A (group quarters)
           1               Public system or private company
           2               Individual drilled well
           3               Individual dug well
           4               Some other source

 SEWAGE             1        50
                           Sewage Disposal
           0               N/A (group quarters)
           1               Public sewer
           2               Septic tank or cesspool
           3               Other means

 AIRCOND            1        51
                           Air Conditioning
           0               N/A (group quarters)
           1               Central system
           2               One individual room unit
           3               Two or more individual room units
           4               None

 HEATING            1        52
                           Heating Equipment
           0               N/A (group quarters)
           1               Steam or hot water system
           2               Central warm-air furnace
           3               Electric heat pump
           4               Other built-in electric units
           5               Floor, wall, or pipeless furnace
           6               Room heaters with flue
           7               Room heaters without flue
           8               Fireplaces, stoves, or portable room heaters
           9               None

 FUELHEAT           1        53
                           House Heating Fuel
           0               N/A (vacant unit or group quarters)
           1               Utility gas from underground pipes serving the
                             neighborhood
           2               Bottle, tank or LP gas
           3               Electricity
           4               Fuel oil, kerosene, etc.
           5               Coal or coke
           6               Wood
           7               Other fuel
           8               No fuel used

 FUELWTR            1        54
                           Water Heating Fuel
           0               N/A (vacant unit or group quarters)
           1               Utility gas from underground pipes serving the
                             neighborhood
           2               Bottle, tank or LP gas
           3               Electricity
           4               Fuel oil, kerosene, etc.
           5               Coal or coke
           6               Wood
           7               Other fuel
           8               No fuel used

 FUELCOOK           1        55
                           Cooking Fuel
           0               N/A (vacant unit or group quarters)
           1               Utility gas from underground pipes serving the
                             neighborhood
           2               Bottle, tank or LP gas
           3               Electricity
           4               Fuel oil, kerosene, etc.
           5               Coal or coke
           6               Wood
           7               Other fuel
           8               No fuel used

 AUTOS              1        56
                           Automobiles Available
           0               N/A (vacant unit or group quarters)
           1               None
           2               One
           3               Two
           4               Three or more

 TRUCKS             1        57
                           Trucks and Vans Available
           0               N/A (vacant unit or group quarters)
           1               None
           2               One
           3               Two
           4               Three or more

 TELEPHON           1        58
                           Telephone in Housing Unit
           0               N/A (vacant unit or group quarters)
           1               With telephone
           2               No telephone

 YRMOVED            1        59
                           Year Householder Moved into Unit
           0               N/A (group quarters or vacant)
           1               1979 to March 1980
           2               1975 to 1978
           3               1970 to 1974
           4               1960 to 1969
           5               1950 to 1959
           6               1949 or earlier

 ACREAGE1           1        60
                           Acreage of Property (H10a on questionnaire-used
                             in determining universe for value and rent)
           0               N/A (group quarters, or two or more units
                             at address)
           1               House on a property of 10 or more acres
           2               House on a property of less than 10 acres
 Positions 61-87

 ACREAGE2           1        61
                           Acreage of Property (H15a on questionnaire-used
                             in determining universe for farm status)
           0               N/A (group quarters)
           1               City or suburban lot, or a place of less than
                             1 acre
           2               1 to 9 acres
           3               10 or more acres

 FARM               1        62
                           Farm Status and Sales of Farm Products
           0               N/A (urban, city or suburban lot, place of less
                             than 1 acre, vacant unit or group quarters)
                           Rural nonfarm (not all rural nonfarm is included):
           1                 $0 to $49
           2                 $50 to $249
           3                 $250 to $599
           4                 $600 to $999
                           Rural farm:
           5                 $1000 to $2499
           6                 $2500 or more

 COMMUSE            1        63
                           Commercial Establishment or Medical Office on
                             Property
           0               N/A (group quarters, or two or more units in
                             structure, mobile home or trailer)
           1               Yes
           2               No

 VALUE              2        64
                           Value
           00              N/A (group quarters; vacant unit except vacant for
                             sale; renter-occupied unit; mobile home or
                             trailer; or noncondominium unit with two or more
                             units at address on 10 or more acres, or with a
                             commercial establishment or medical office on
                             property)
           01              Less than $10,000
           02              $10,000 to $14,999
           03              $15,000 to $17,499
           04              $17,500 to $19,999
           05              $20,000 to $22,499
           06              $22,500 to $24,999
           07              $25,000 to $27,499
           08              $27,500 to $29,000
           09              $30,000 to $34,999
           10              $35,000 to $39,999
           11              $40,000 to $44,999
           12              $45,000 to $49,999
           13              $50,000 to $54,999
           14              $55,000 to $59,999
           15              $60,000 to $64,999
           16              $65,000 to $69,999
           17              $70,000 to $74,999
           18              $75,000 to $79,999
           19              $80,000 to $89,999
           20              $90,000 to $99,999
           21              $100,000 to $124,999
           22              $125,000 to $149,999
           23              $150,000 to $199,999
           24              $200,000 or more

 ELECPAID           2        66
                           Payment of Electricity
           0               N/A (vacant unit or group quarters)
           1               Electricity paid, amount shown in ELECOST
           2               Included in rent or no charge
           3               Electricity not used

 ELECOST            3        67
                           Monthly Cost of Electricity
          000              N/A (vacant unit, group quarters, or no payment
                             for electricity)
        001-199            Cost in dollars
          200              $200 or more

 GASPAID            1        70
                           Payment of Gas
           0               N/A (vacant unit or group quarters)
           1               Gas paid, amount shown in GASCOST
           2               Included in rent or no charge
           3               Gas not used

 GASCOST            3        71
                           Monthly Cost of Gas
          000              N/A (vacant unit, group quarters, or no payment
                             for gas)
        001-149            Cost in dollars
          150              $150 or more

 WTRPAID            1        74
                           Payment of Water
           0               N/A (vacant unit or group quarters)
           1               Water paid, amount shown in WTRCOST
           2               Included in rent or no charge
 WTRCOST            3        75
                           Monthly Cost of Water
          000              N/A (vacant unit, group quarters, or no payment
                             for water)
        001-499            Cost in dollars
          500              $500 or more

 FUELPAID           1        78
                           Payment of Oil, Coal, Kerosene, Wood, etc.
           0               N/A (vacant unit or group quarters)
           1               Fuels paid, amount shown in FUELCOST
           2               Included in rent or no charge
           3               These fuels not used

 FUELCOST           4        79
                           Yearly Cost of Oil, Coal, Kerosene, Wood, etc.
          0000             N/A (vacant unit, group quarters, or no payment
                             for these fuels)
        0001-1999          Cost in dollars
          2000             $2000 or more

 TAXINSUR           4        83
                           Real Estate Taxes Last Year and Yearly
                             Property Insurance Premiums, Combined
          0000             No tax or insurance payments, or N/A (renter-
                             occupied unit, vacant unit, unit on 10 or more
                             acres, unit with a commercial establishment or
                             medical office on property, two or more units in
                             structure, mobile home or trailer, condominium,
                             or group quarters)
        0001-2999          Taxes plus insurance premiums in dollars
          3000             $3000 or more

 MORTGAG1           1        87
                           Mortgage Status
           0               N/A (see TAXINSUR)
           1               Yes, mortgage, deed of trust or similar debt
           2               Yes, contract to purchase
           3               No
 Positions 88-107

 MORTGAG2           1        88
                           Second or Junior Mortgage
           0               N/A (no mortgage, deed of trust, contract to
                             purchase or similar debt on this property, and
                             others in TAXINSUR)
           1               Yes
           2               No

 MORTGAG3           4        89
                           Total Monthly Payment to Lender
          0000             No regular payments required or N/A
                             (units with no mortgage and others in TAXINSUR)
        0001-1499          Payment in dollars
          1500             $1500 or more

 TAXINCL            1        93
                           Inclusion of Real Estate Taxes in Payment to Lender
           0               N/A (no regular payment required and
                             others in MORTGAG2)
           1               Yes, payment includes taxes
           2               No

 INSINCL            1        94
                           Inclusion of Insurance Premiums in Payment to
                             Lender
           0               N/A (see TAXINCL)
           1               Yes, payment includes insurance premiums
           2               No

 OWNERCST           4        95
                           Selected Monthly Owner Costs
          0000             N/A (renter-occupied unit, vacant unit, unit on
                             10 or more acres, unit with a commercial
                             establishment or medical office on property,
                             two or more units in structure, mobile home or
                             trailer, condominium, or group quarters)
        0001-1999          Cost in dollars
          2000             $2000 or more

 RENT1              2        99
                           Contract Rent
           00              N/A (owner-occupied unit, vacant unit except vacant
                             for rent, unit on 10 or more acres with one unit
                             at address, or group quarters)
           01              Less than $50
           02              $50 to $59
           03              $60 to $69
           04              $70 to $79
           05              $80 to $89
           06              $90 to $99
           07              $100 to $109
           08              $110 to $119
           09              $120 to $129
           10              $130 to $139
           11              $140 to $149
           12              $150 to $159
           13              $160 to $169
           14              $170 to $179
           15              $180 to $189
           16              $190 to $199
           17              $200 to $224
           18              $225 to $249
           19              $250 to $274
           20              $275 to $299
           21              $300 to $349
           22              $350 to $399
           23              $400 to $499
           24              $500 or more
           25              No cash rent

 RENT2              3       101
                           Gross Rent
           000             N/A (owner-occupied unit, unit rented without
                             payment of cash rent, vacant unit, unit on 10 or
                             more acres with one unit at address, or group
                             quarters)
         001-998           Gross rent in dollars
           999             $999 or more

 HHTYPE             1       104
                           Household Type
           0               N/A (vacant unit or group quarters)
           1               Married-couple family household
           2               Family household with male householder, no wife
                             present
           3               Family household with female householder, no
                             husband present
           4               Nonfamily household

 CHILDREN           1       105
                           Presence and Age of Own Children
           0               N/A (nonfamily household, vacant unit or group
                             quarters)
           1               Family with own children under 6 years only
           2               Family with own children 6 to 17 years only
           3               Family with own children, some 6 to 17 years, and
                             some under 6 years
           4               Family without own children

 NSUBFAM            1       106
                           Number of Subfamilies in Family
           0               None or N/A (vacant unit or group quarters)
           1               One subfamily
           2               Two subfamilies
           3               Three subfamilies
           4               Four subfamilies

 HHINCOME           1       107
                           Household Income in 1979
         00000             No income/loss or N/A (vacant unit or group
                             quarters)
         -9995             Loss of $9990 or more
     -9985 to 74995        Income (or loss) in dollars
         75000             Income of $75000 or more
 Positions 112-140

 FAMINCOM           5       112
                           Family Income in 1979
         00000             No income/loss or N/A (nonfamily household, vacant
                             unit or group quarters)
         -9995             Loss of $9990 or more
     -9985 to 74995        Income (or loss) in dollars
         75000             Income of $75000 or more

 AGQTYPE            1       117
                           Allocation of Type of Group Quarters
           0               Not allocated or N/A
           1               Allocated, assigned

 ATENURE            1       118
                           Allocation of Tenure
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AVAC1              1       119
                           Allocation of Seasonal and Migratory
                             Vacancy Status
           0               Not allocated or N/A
           1               Allocated, assigned

 AVAC2              1       120
                           Allocation of Vacancy Type
           0               Not allocated or N/A
           1               Allocated, assigned

 AVAC3              1       121
                           Allocation of Boarded Up Status
           0               Not allocated or N/A
           1               Allocated, assigned

 AVAC4              1       122
                           Allocation of Duration of Vacancy
           0               Not allocated or N/A
           1               Allocated, hot deck

 ACONDO             1       123
                           Allocation of Condominium Status
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned
           3               Allocated, structure edit

 AUNITS1            1       124
                           Allocation of Units in Structure
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AUNITS2            1       125
                           Allocation of Units at Address
           0               Not allocated or N/A
           1               Allocated, hot deck

 AACCESS            1       126
                           Allocation of Access
           0               Not allocated or N/A
           1               Allocated, assigned

 AYRBUILT           1       127
                           Allocation of Year Structure Built
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 ASTORIES           1       128
                           Allocation of Stories in Structure
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AELEVATO           1       129
                           Allocation of Passenger Elevator
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AROOMS             1       130
                           Allocation of Rooms
           0               Not allocated or N/A
           1               Allocated, hot deck

 ABEDROOM           1       131
                           Allocation of Bedrooms
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 APLUMBIN           1       132
                           Allocation of Plumbing Facilities
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AKITCHEN           1       133
                           Allocation of Kitchen Facilities
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 ABATHROO           1       134
                           Allocation of Bathrooms
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AWATER             1       135
                           Allocation of Source of Water
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 ASEWAGE            1       136
                           Allocation of Sewage Disposal
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AAIRCOND           1       137
                           Allocation of Air Conditioning
           0               Not allocated or N/A
           1               Allocated, hot deck

 AHEATING           1       138
                           Allocation of Heating Equipment
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AFUELHEA           1       139
                           Allocation of House Heating Fuel
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AFUELWTR           1       140
                           Allocation of Water Heating Fuel
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned
 Positions 141-163

 AFUELCOO           1       141
                           Allocation of Cooking Fuel
           0               Not allocated or N/A
           1               Allocated, hot deck

 AAUTOS             1       142
                           Allocation of Automobiles Available
           0               Not allocated or N/A
           1               Allocated, hot deck

 ATRUCKS            1       143
                           Allocation of Trucks and Vans
           0               Not allocated or N/A
           1               Allocated, hot deck

 ATELEPHO           1       144
                           Allocation of Telephone in Housing Unit
           0               Not allocated or N/A
           1               Allocated, hot deck

 AYRMOVED           1       145
                           Allocation of Year Householder Moved Into Unit
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AACRE1             1       146
                           Allocation of Acreage of Property (H10a on
                             questionnaire)
           0               Not allocated or N/A
           1               Allocated, hot deck

 AACRE2             1       147
                           Allocation of Acreage of Property (H15a on
                             questionnaire)
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AFARM              1       148
                           Allocation of Farm Status and Sales of Farm
                             Products
           0               Not allocated or N/A
           1               Allocated, hot deck

 ACOMMERC           1       149
                           Allocation of Commercial Establishment or
                             Medical Office
           0               Not allocated or N/A
           1               Allocated, hot deck

 AVALUE             1       150
                           Allocation of Value
           0               Not allocated or N/A
           1               Allocated, hot deck

 AELECCOS           1       151
                           Allocation of Monthly Cost of Electricity
           0               Not allocated or N/A
           1               Allocated, hot deck

 AGASCOST           1       152
                           Allocation of Monthly Cost of Gas
           0               Not allocated or N/A
           1               Allocated, hot deck

 AWTRCOST           1       153
                           Allocation of Yearly Cost of Water
           0               Not allocated or N/A
           1               Allocated, hot deck

 AFUELCOS           1       154
                           Allocation of Yearly Cost of Oil, Coal, Kerosene,
                             Wood, etc.
           0               Not allocated or N/A
           1               Allocated, hot deck

 ATAX               1       155
                           Allocation of Real Estate Taxes
           0               Not allocated or N/A
           1               Allocated, hot deck

 AINSUR             1       156
                           Allocation of Yearly Insurance Premium
           0               Not allocated or N/A
           1               Allocated, hot deck

 AMORTG1            1       157
                           Allocation of Mortgage Status
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AMORTG2            1       158
                           Allocation of Second or Junior Mortgage
           0               Not allocated or N/A
           1               Allocated, hot deck

 AMORTG3            1       159
                           Allocation of Total Monthly Payment to Lender
           0               Not allocated or N/A
           1               Allocated, hot deck

 ATAXINCL           1       160
                           Allocation of Inclusion of Taxes in Payment
                             to Lender
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 AINSINCL           1       161
                           Allocation of Inclusion of Insurance Premiums in
                             Payment to Lender
           0               Not allocated or N/A
           1               Allocated, hot deck
           2               Allocated, assigned

 ARENT1             1       162
                           Allocation of Contract Rent
           0               Not allocated or N/A
           1               Allocated, hot deck

 FILLER            31       163
                           Zero fill
PUMSP Data Dictionary

 Record P
  Positions 1-40
                  SIZE/
 NAME             SCALE   BEGIN

 RECTYPE            1         1
                           Record Type
           P               Person Record

 RELAT1             2         2
                           Relationship
           00              Householder
                           Family member other than householder:
           01                Spouse
           02                Child
           03                Brother or sister
           04                Parent
           05                Other relative (See RELAT2)
                           Person not related to householder:
           06                Roomer or boarder
           07                Partner or roommate
           08                Paid employee
           09                Other nonrelative
                           In group quarters:
           10                Inmate
           11                Noninmate

 RELAT2             1         4
                           Detailed Relationship
           0               N/A (person not listed as "other relative" of
                             householder)
           1               Son-in-law or daughter-in-law
           2               Grandchild
           3               Father-in-law or mother-in-law
           4               Brother-in-law or sister-in-law
           5               Nephew or niece
           6               Grandparent
           7               Uncle or aunt
           8               Cousin
           9               Other person related by blood or marriage

 SUBFAM1            1         5
                           Subfamily Relationship
           0               N/A (group quarters or not in a subfamily)
           1               Husband/wife in married-couple subfamily
           2               Parent in parent-child subfamily
           3               Child in subfamily

 SUBFAM2            1         6
                           Subfamily Number
           0               N/A (group quarters or not in a subfamily)
           1               In subfamily #1
           2               In subfamily #2
           3               In subfamily #3
           4               In subfamily #4

 SEX                1         7
                           Sex
           0               Male
           1               Female

 AGE                2         8
                           Age
         00-89             Age in years
           90              90 years or more

 QTRBIRTH           1        10
                           Quarter of Birth
           0               January-March
           1               April-June
           2               July-September
           3               October-December

 MARITAL            1        11
                           Marital Status
           0               Now married, except separated
           1               Widowed
           2               Divorced
           3               Separated
           4               Single or N/A (under 15 years of age)

 RACE               2        12
                           Race
           01              White
           02              Black
           03              American Indian, Eskimo, Aleut
                           Asian and Pacific Islander:
           04                Japanese
           05                Chinese
           06                Filipino
           07                Korean
           08                Asian Indian
           09                Vietnamese
           10                Hawaiian
           11                Other Asian and Pacific Islander, including
                               Guamanian and Samoan
                           Other (Race n.e.c.):
           12                Spanish write-in entry
           13                Other

 SPANISH            1        14
                           Spanish Origin
           0               N/A (not of Spanish origin)
           1               Mexican
           2               Puerto Rican
           3               Cuban
           4               Other Spanish

 SURNAME            1        15
                           Spanish Surname
           0               N/A (not in Arizona, California, Colorado, New
                             Mexico, or Texas; in Bowie County, Texas on
                             B sample)
           1               Spanish surname
           2               Not Spanish surname
           3               Not reported

 ANCSTRY1           3        16
                           Ancestry-First Entry
        001-999            See App. E

 ANCSTRY2           3        19
                           Ancestry-Second Entry
        001-919            See App. E

 BIRTHPL            3        22
                           Place of Birth
        001-056            FIPS state code (See App. A)
        060-997            Foreign country or outlying area of the U.S.
                             (See App. F)

 CITIZEN            1        25
                           Citizenship
           0               Born in the United States or outlying areas
           1               Naturalized citizen
           2               Not a citizen
           3               Born abroad of American parents

 IMMIGR             1        26
                           Year of Immigration
           0               N/A (born in the United States of outlying areas
                             or born abroad of American parents)
           1               1975 to 1980
           2               1970 to 1974
           3               1965 to 1969
           4               1960 to 1964
           5               1950 to 1959
           6               Before 1950

 LANG1              1        26
                           Language Usage
           0               N/A (under 3 years of age)
           1               Speak a language other than English at home
           2               Speak only English at home

 LANG2              3        28
                           Language Spoken at Home
          000              N/A (under 3 years of age or speaks only English)
        011-997            Language code (See App. G)
          998              Language not reported

 ENGLISH            1        31
                           Ability to Speak english
           0               N/A (Speaks only English or under 3 years of age)
           1               Very well
           2               Well
           3               Not well
           4               Not at all

 FERTILTY           2        32
                           Children Ever Born
           00              N/A (under 15 years of age or male)
           01              None
           02              One
           03              Two
           04              Three
           05              Four
           06              Five
           07              Six
           08              Seven
           09              Eight
           10              Nine
           11              Ten
           12              Eleven
           13              Twelve or more

 TIMESMAR           1        34
                           Times Married
           0               N/A (under 15 years of age or never married)
           1               Once
           2               More than once

 AGEMAR             2        35
                           Age at First Marriage
           00              N/A (under 15 years of age or never married)
         12-89             Age at first marriage in years
           90              90 years or over at first marriage

 QTRMAR             1        37
                           Quarter of First Marriage
           0               N/A (under 15 years of age or never married)
           1               January-March
           2               April-June
           3               July-September
           4               October-December

 WIDOWED            1        38
                           Widowed
           0               N/A (under 15 years of age, never married, or
                             not married more than once)
           1               First marriage ended because of death of spouse
           2               Not widowed

 SCHOOL             1        39
                           School Enrollment and Type of School
           0               Not enrolled in school or N/A (under 3 years
                             of age)
                           Enrolled in school:
           1                 Public
           2                 Church-related
           3                 Other private

 GRADE              2        40
                           Highest Year of School Attended
           00              Never attended school or N/A (under 3 years
                             of age)
           01              Nursery school
           02              Kindergarten
                           Elementary:
           03                First grade
           04                Second grade
           05                Third grade
           06                Fourth grade
           07                Fifth grade
           08                Sixth grade
           09                Seventh grade
           10                Eighth grade
                           High school:
           11                Ninth grade
           12                Tenth grade
           13                Eleventh grade
           14                Twelfth grade
                           College:
           15                First year
           16                Second year
           17                Third year
           18                Fourth year
           19                Fifth year
           20                Sixth year
           21                Seventh year
           22                Eighth year or more
 Positions 42-80

 FINGRADE           1        42
                           Finished Highest Grade
           0               Never attended school or N/A (under 3 years
                             of age)
           1               Now attending this grade
           2               Finished this grade
           3               Did not finish this grade

 AF75               1        43
                           Activity in 1975:  in Armed Forces
           0               N/A (under 16 years of age)
           1               Yes
           2               No (includes all persons 16-20)

 COLL75             1        44
                           Activity in 1975:  Attending College
           0               N/A (under 16 years of age)
           1               Yes
           2               No (includes all persons 16-20)

 WORK75             1        45
                           Activity in 1975:  Working at a Job or
                             Business
           0               N/A (under 16 years of age)
           1               Yes, full time
           2               Yes, part time
           3               No (includes all persons 16-20)

 MIGWGT             1        46
                           Migration/Place of Work/Travel Time Weight
           0               N/A (not included in migration/place of work/
                             travel time sample, i.e., no data for
                             following 10 items)
           2               In migration/place of work/travel time sample

 STATE75            2        47
                           Residence in 1975:  State
           00              N/A (not included in migration/place of work/
                             travel time sample, or born April 1975 or
                             later)
         01-56             FIPS state code (See App. A)
         61-68             State group code (selected states on C Sample-
                             See App. A)
           72              Puerto Rico
           73              U.S. outlying area
           97              Abroad
           98              Same house
           99              State not identified (selected county groups on
                             B Sample-See App. C)

 COGRP75              3        49
                           Residence in 1975:  County Group (A and B Samples)
           000             N/A (C Sample, not included in migration/place of
                             work/travel time sample, born April 1975 or
                             later, or living abroad in 1975)
         001-998           County group code
           999             Same house

 MIG75                1        52
                           Residence in 1975:  State-County Recode
           0               N/A (not included in migration/place of
                             work/travel time sample, born April 1975 or
                             later)
           1               Same house
                           Different house:
           2                 Same county
                           Different county:
           3                 Same state
                           Different state:
           4                 Region not specified (B Sample only)
           5               Northeast (A, C Samples only)
           6               North Central (A, C Samples only)
           7               South (A, C Samples only)
           8               West (A, C Samples only)
           9               Abroad

 METRO75              2        53
                           Residence in 1975:  SMSA Recode
           00              N/A (C Sample, not included in migration/place of
                             work/travel time sample, born April 1975 or
                             later)
           01              Living in same house in 1975
                           Living in SMSA in 1980 (not applicable if
                                 AREATYPE=4, mixed metro/nonmetro areas on
                                 A Sample):
                             Different house in same SMSA:
           02                  In central city(s)
           03                  Outside central city(s)
                             Different house in different SMSA:
           04                  In central city(s)
           05                  Outside central city(s)
           06                Outside any SMSA, or abroad
                           Living outside SMSA in 1980 (not applicable if
                                 AREATYPE=4, mixed metro/nonmetro areas on
                                 A Sample):
           07                Different house in central city of an SMSA
           08                Different house in SMSA, outside central city
           09                Outside an SMSA, or abroad
           10              Living in a mixed metro/nonmetro area in 1980,
                                 different house (A Sample only)

 POWSTATE           2        55
                           Place of Work:  State
           00              N/A (not included in migration/place of work/
                             travel time sample, under 16 years of age,
                             not at work)
          1-56             FIPS state code (See App. A)
         61-68             State group code (selected states on C Sample-
                             See App. A)
           72              Puerto Rico
           73              U.S. outlying area
           97              Abroad
           98              State and/or county not reported
           99              State not identified (selected county groups on
                             B Sample-See App. C)

 POWCOGRP           3        57
                           Place of Work:  County Group (A and B samples)
           000             N/A (C Sample; not included in migration/place of
                             work/travel time sample, under 16 years of age;
                             not at work; place of work in outlying area or
                             foreign country, abroad, at sea, or state and/
                             or county not reported)
         001-998           County group code

                           Note:  In New York (state code = 36) county group
                                  code 099 indicates "New York City, county
                                  not specified" on both A and B samples.
                                  This applies only to place of work.

 POWMETRO           1        60
                           Place of Work:  SMSA Recode (A and B samples)
           0               N/A (C Sample; not included in migration/place of
                             work/travel time sample; under 16 years of age;
                             not at work; place of work in outlying area or
                             foreign country, abroad, at sea, or state and/
                             or county not reported)
                           Living in SMSA (not applicable if
                                 AREATYPE=4, mixed metro/nonmetro area on
                                 A Sample):
                             Working in same SMSA:
           1                   In CBD
           2                   In remainder of central city
           3                   Outside central city
                             Working in different SMSA:
           4                   In central city
           5                   Outside central city
           6                   Working outside any SMSA
                           Living outside SMSA or in a mixed metro/nonmetro
                             area (AREATYPE=4, A Sample only):
           7                 Working in central city of an SMSA
           8                 Working in an SMSA, outside central city
           9                 Working outside any SMSA

 POWCC              1        61
                           Place of Work:  Central City Recode (C Sample only)
           0               N/A (A and B Samples; not in migration/place of
                             work/travel time sample; under 16 years of age;
                             not at work; place of work in outlying area or
                             foreign country, abroad, at sea, or state and/
                             or county not reported)
           1               Working in the CBD of a UA central city
           2               Working in the remainder of a central city of a
                             UA (or anywhere in a central city with no CBD)
           3               Working elsewhere

 POWPLSIZ           1        62
                           Place of Work:  Place Size (C Sample only)
           0               N/A (A or B Sample; not in migration/place of
                             work/travel time sample; under 16 years of age;
                             not at work; place of work in outlying area or
                             foreign country, abroad, at sea, or state and/
                             or county not reported)
           1               2,500 to 9,999
           2               10,000 to 24,999
           3               25,000 to 49,999
           4               50,000 or more
           5               Not in an identified place of 2,500 or more, or
                             not reported at the place level

 TIME               2        63
                           Travel Time to Work
           00              N/A (not included in migration/place of
                             work/travel time sample; under 16 years of age;
                             not at work; or worked at home)
          1-98             Time in minutes
           99              99 minutes or more

 MEANS              2        65
                           Means of Transportation to Work
           00              N/A (under 16 years of age or not at work)
                           Private vehicle:
           01                Car
           02                Truck
           03                Van
                           Public transportation:
           04                Bus or streetcar
           05                Railroad
           06                Subway or elevated
           07                Taxicab
           08              Motorcycle
           09              Bicycle
           10              Walked only
           11              Worked at home
           12              Other means

 CARPOOL            1        67
                           Carpooling
           0               N/A (under 16 years of age, not at work, means
                             of transportation to work other than car,
                             truck, or van)
           1               Drive alone
                           Carpool:
           2                 Share driving
           3                 Drive others only
           4                 Ride as passenger only

 RIDERS             1        68
                           Carpool Occupancy
           0               N/A (under 16 years of age, not at work, drives
                             along to work,  means of transportation to work
                             other than car, truck, or van)
           1               Two
           2               Three
           3               Four
           4               Five
           5               Six
           6               Seven or more

 DISABIL1           1        69
                           Work Disability Status:  Limited
           0               N/A (under 16 years of age)
           1               With a work disability
           2               No work disability

 DISABIL2           1        70
                           Work Disability Status:  Prevented from Working
           0               N/A (under 16 years of age)
           1               Prevented from working
           2               Not prevented from working

 DISABIL3           1        71
                           Public Transportation Disability Status
           0               N/A (under 16 years of age)
           1               With a public transportation disability
           2               No public transportation disability

 VETERAN1           1        72
                           Veteran Status
           0               Veteran of active-duty military service
           1               Not a veteran or N/A (under 16 years of age)

 VETERAN2           1        73
                           Period of Service May 1975 or Later
           0               No or N/A (under 16 years of age)
           1               Yes

 VETERAN3           1        74
                           Period of Service During Vietnam Era (August
                             1964-April 1975)
           0               No or N/A (under 16 years of age)
           1               Yes

 VETERAN4           1        75
                           Period of Service Between February 1955 and
                             July 1964)
           0               No or N/A (under 16 years of age)
           1               Yes

 VETERAN5           1        76
                           Period of Service During Korean Conflict
                             (June 1950-January 1955)
           0               No or N/A (under 16 years of age)
           1               Yes

 VETERAN6           1        77
                           Period of Service During World War II
                             (September 1940-July 1947)
           0               No or N/A (under 16 years of age)
           1               Yes

 VETERAN7           1        78
                           Period of Service During World War I
                             (April 1917-November 1918)
           0               No or N/A (under 16 years of age)
           1               Yes

 VETERAN8           1        79
                           Period of Service During Any Other Time
           0               No or N/A (under 16 years of age)
           1               Yes

 YEARWORK           1        80
                           Year Last Worked
           0               N/A (under 16 years of age)
           1               1980
           2               1979
           3               1978
           4               1975-1977
           5               1970-1974
           6               1969 or earlier
           7               Never worked
 Positions 81-134
 
 LABOR              1        81
                           Labor Force Status
           0               N/A (under 16 years of age)
                           In labor force:
                             Civilian labor force:
                               Employed:
           1                     At work
           2                     With a job but not at work
           3                   Unemployed
                             Armed Forces:
           4                     At work
           5                     With a job but not at work
           6                 Not in labor force

 HOURS              2        82
                           Hours Worked Last Week
           00              N/A (under 16 years of age or not at work)
          1-98             Hours worked last week
           99              99 or more hours worked last week

 ABSENT             1        84
                           Absent from Work Last Week
           0               N/A (under 16 years of age or at work)
           1               Yes, on layoff
           2               Yes, on vacation, temporary illness, labor
                             dispute, etc.
           3               No
           4               Not reported

 LOOKING            1        85
                           Looking For Work
           0               N/A (under 16 years of age or at work)
           1               Yes
           2               No
           3               Not reported

 ABLE               1        86
                           Able to Take Job Last Week
           0               N/A (under 16 years of age, at work or not
                             looking for work)
           1               No, already had a job
           2               No, temporarily ill
           3               No, other reasons (in school, etc.)

           4               Yes, could have taken a job
           5               Not reported

 INDUSTRY           3        87
                           Industry
          000              N/A (under 16 years of age, in Armed Forces,
                             last worked before 1975 and not in labor force,
                             or never worked)
        010-992            Industry code (See App. G)

 OCCUP              3        90
                           Occupation
          000              N/A (under 16 years of age, in Armed Forces,
                             last worked before 1975 and not in labor force,
                             or never worked)
        003-909            Occupation code (See App. H)

 CLASS              1        93
                           Class of Worker
           0               N/A (under 16 years of age, last worked before
                             1975, or never worked)
           1               Private wage and salary worker:
                             Employee of private company
           2               Federal government worker
           3               State government worker
           4               Local government worker
           5               Self-employed worker--business not incorporated
           6               Employee of own corporation
           7               Unpaid family worker

 WORK79             1        94
                           Work Last Year
           0               N/A (under 16 years of age)
           1               Worked in 1979
           2               Did not work in 1979

 WEEKSW79           2        95
                           Weeks Worked in 1979
           00              N/A (under 16 years of age or did not work
                             in 1979)
          00-52            Weeks worked

 HOURS79            2        97
                           Usual Hours Worked Per Week in 1979
           00              N/A (under 16 years of age or did not work
                             in 1979)
          01-98            Usual number of hours
           99              99 or more hours per week

 WEEKSU79           2        99
                           Weeks Unemployed in 1979
           00              N/A (under 16 years of age or with no
                             unemployment in 1979)
          01-52            Weeks looking for work or on layoff

 INCOME1            5       101
                           Wage or Salary Income in 1979
          00000            N/A (under 16 years of age or no
                             income from this source)
       00005-74995         Income in dollars (midpoint of $10 interval)
          75000            Income of $75000 or more

 INCOME2            5       106
                           Nonfarm Self-Employment Income in 1979
          00000            N/A (under 16 years of age or no
                             income/loss from this source)
          -9995            Loss of $9990 or more
      -9985 to 74995       Income (or loss) in dollars (midpoint of $10
                             interval)
          75000            Income of $75000 or more

 INCOME3            5       111
                           Farm Self-Employment Income in 1979
          00000            N/A (under 16 years of age or no
                             income/loss from this source)
          -9995            Loss of $9990 or more
      -9985 to 74995       Income (or loss) in dollars (midpoint of $10
                             interval)
          75000            Income of $75000 or more

 INCOME4            5       116
                           Interest, Dividend or Net Rental Income in 1979
          00000            N/A (under 15 years of age or no
                             income/loss from this source)
          -9995            Loss of $9990 or more
      -9985 to 74995       Income (or loss) in dollars (midpoint of $10
                             interval)
          75000            Income of $75000 or more

 INCOME5            4       121
                           Social Security Income in 1979
          0000             N/A (under 15 years of age or no
                             income from this source)
        0005-9995          Income in dollars (midpoint of $10 interval)

 INCOME6            4       125
                           Public Assistance Income in 1979
          0000             N/A (under 15 years of age or no
                             income from this source)
        0005-9995          Income in dollars (midpoint of $10 interval)

 INCOME7            5       129
                           All Other Income in 1979
          00000            N/A (under 15 years of age or no
                             income from sources other than those
                             separately identified)
       00005-74995         Income in dollars (midpoint of $10 interval)
          75000            Income of $75000 or more

 INCOME8            5       134
                           Income From All Sources in 1979
          00000            N/A (under 15 years of age or no
                             income/loss from any source)
          -9995            Loss of $9990 or more
      -9985 to 74995       Income (or loss) in dollars
          75000            Income of $75000 or more
 Positions 139-170

 POVERTY            1       139
                           Poverty Status in 1979 (Ratio of Family or
                             Unrelated Individual Income in 1979 to
                             Poverty Cutoff)
           0               N/A (inmate of institution, person in military
                             group quarters or in college dormitory, or
                             unrelated individual under 15 years of age)
                           Below poverty level:
           1                 Below .75 of poverty cutoff (including no income
                               or net loss)
           2                 .75 to .99
                           Above poverty level:
           3               1.00 to 1.24
           4               1.25 to 1.49
           5               1.50 to 1.74
           6               1.75 to 1.99
           7               2.00 or more

 ARELAT1            1       140
                           Allocation of Household Relationship
           0               Not allocated
           1               Allocated, consistency edit (in GQ:  cold deck)
           2               Allocated, hot deck (in households only)

 ARELAT2            1       141
                           Allocation of Detailed Relationship
           0               Not allocated
           1               Allocated

 ASEX               1       142
                           Allocation of Sex
           0               Not allocated
           1               Allocated, consistency edit (in GQ:  allocated)
           2               Allocated, hot deck (in households only)

 AAGE               1       143
                           Allocation of Age
           0               Not allocated
           1               Allocated, hot deck (in GQ:  cold deck)
           2               Allocated, hot deck (in GQ only)

 AQTRBRTH           1       144
                           Allocation of Quarter of Birth
           0               Not allocated
           1               Allocated, cold deck

 AMARITAL           1       145
                           Allocation of Marital Status
           0               Not allocated or N/A
           1               Yes, consistency edit
           2               Yes, hot deck

 ARACE1             1       146
                           Allocation of Race
           0               Not allocated
           1               Allocated from relative, this household
                             (in GQ:  cold deck)
           2               Allocated from nonrelative, this household
                             (in GQ:  hot deck)
           3               Allocated, hot deck (in households only)

 ARACE2             1       147
                           Pre-edit of Detailed Race and American Indian
           0               Not allocated
           1               Allocated:  pre-edit

 ASPANISH           1       148
                           Allocation of Spanish Origin
           0               Not allocated
           1               Allocated from information for this person or
                             from relative, this household
                             (in GQ:  allocation)
           2               Allocated from nonrelative, this household
                             (in household only)
           3               Allocated from information for this person or from
                             hot deck, different household (in
                             households only)

 AANCSTRY           1       149
                           Pre-edit of Ancestry (both 1st and 2nd entry)
           0               Not allocated
           1               Allocated:  pre-edit

 ABIRTHPL           1       150
                           Allocation of Place of Birth
           0               Not allocated
           1               Allocated:  pre-edit
           2               Allocated, consistency edit
           3               Allocated, hot deck

 ACITIZEN           1       151
                           Allocation of Citizenship
           0               Not allocated
           2               Yes, consistency edit
           3               Yes, hot deck

 AIMMIGR            1       152
                           Allocation of Year of Immigration
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 ALANG1             1       153
                           Allocation of Language Usage
           0               Not allocated or N/A
           2               Yes, consistency edit*
           3               Yes, hot deck

 ALANG2             1       154
                           Allocation of Language Spoken at Home
           0               Not allocated or N/A
           1               Allocated:  pre-edit
           2               Allocated, consistency edit
           3               Allocated, hot deck

 ALANG3             1       155
                           Allocation of Ability to Speak English
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AFERTIL            1       156
                           Allocation of Children Ever Born
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 ATIMESMA           1       157
                           Allocation of Times Married
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AAGEMR             1       158
                           Allocation of Age at First Marriage and
                             Quarter of First Marriage
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AWIDOWED           1       159
                           Allocation of Widowed
           0               Not allocated or N/A
           3               Allocated, hot deck

 ASCHOOL            1       160
                           Allocation of School Enrollment and Type
                             of School
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AYEARSCH           1       161
                           Allocation of Highest Year of School Attended
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AFINGRAD           1       162
                           Allocation of Finished Grade
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AAF75              1       163
                           Allocation of Activity in 1975:  in Armed Forces
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck


 ACOLL75            1       164
                           Allocation of Activity in 1975:  Attending College
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AWORK75            1       165
                           Allocation of Activity in 1975:  Working at a Job
                             or Business
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AMIG751            1       166
                           Allocation of Residence in 1975:  Same House/
                             Different House
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AMIG752            1       167
                           Allocation of Residence in 1975:  Specific Area
           0               Not allocated or N/A
           1               Allocated:  pre-edit
           2               Allocated, consistency edit
           3               Allocated, hot deck

 ATIME              1       168
                           Allocation of Travel Time to Work
           0               Not allocated or N/A
           3               Allocated, hot deck

 AMEANS             1       169
                           Allocation of Means of Transportation to Work
           0               Not allocated or N/A
           3               Allocated, hot deck

 ACARPOOL           1       170
                           Allocation of Carpooling
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck
 Positions 171-193

 ARIDERS            1       171
                           Allocation of Carpool Occupancy
           0               Not allocated or N/A
           3               Allocated, hot deck

 ADISABL1           1       172
                           Allocation of Work Disability Status:  Limited
           0               Not allocated or N/A
           2               Yes, consistency edit*
           3               Yes, hot deck

 ADISABL2           1       173
                           Allocation of Work Disability Status:  Prevented
                             from Working
           0               Not allocated or N/A
           2               Yes, consistency edit*
           3               Yes, hot deck

 ADISABL3           1       174
                           Allocation of Public Transportation Disability
                             Status
           0               Not allocated or N/A
           3               Yes, hot deck

 AVET1              1       175
                           Allocation of Veteran Status
           0               Not allocated or N/A
           2               Yes, consistency edit*
           3               Yes, hot deck

 AVET2              1       176
                           Allocation of Veterans' Period of Service
           0               Not allocated or N/A
           3               Allocated, hot deck

 AYEARWRK           1       177
                           Allocation of Year Last Worked
           0               Not allocated or N/A
           2               Yes, consistency edit*
           3               Yes, hot deck

 ALABOR             1       178
                           Allocation of Labor Force Status
           0               Not allocated or N/A
           3               Allocated, hot deck

 AHOURS             1       179
                           Allocation of Hours Worked Last Week
           0               Not allocated or N/A
           3               Allocated, hot deck

 AINDUSTR           1       180
                           Allocation of Industry
           0               Not allocated or N/A
           1               Allocated:  pre-edit
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 AOCCUP             1       181
                           Allocation of Occupation
           0               Not allocated or N/A
           1               Allocated:  pre-edit
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 ACLASS             1       182
                           Allocation of Class of Worker
           0               Not allocated or N/A
           2               Yes, consistency edit*
           3               Yes, hot deck

 AWORK79            1       183
                           Allocation of Work Last Year
           0               Not allocated or N/A
           2               Yes, consistency edit
           3               Yes, hot deck

 AWEEKW79           1       184
                           Allocation of Weeks Worked in 1979
           0               Not allocated or N/A
           2               Yes, consistency edit*
           3               Yes, hot deck

 AHOUR79            1       185
                           Allocation of Usual Hours Worked Per Week in 1979
           0               Not allocated or N/A
           3               Allocated, hot deck

 AWEEKU79           1       186
                           Allocation of Weeks Unemployed in 1979
           0               Not allocated or N/A
           1               Allocated:  pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 AINCOME1           1       187
                           Allocation of Wage or Salary Income in 1979
           0               Not allocated or N/A
           1               Allocated:  pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 AINCOME2           1       188
                           Allocation of Nonfarm Self-Employment Income in
                            1979
           0               Not allocated or N/A
           1               Allocated:  pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 AINCOME3           1       189
                           Allocation of Farm Self-Employment Income in
                            1979
           0               Not allocated or N/A
           1               Allocated:  pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck


 AINCOME4           1       190
                           Allocation of Interest, Dividend or Net Rental
                            Income in 1979
           0               Not allocated or N/A
           1               Allocated:  pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 AINCOME5           1       191
                           Allocation of Social Security Income in 1979
           0               Not allocated or N/A
           1               Allocated:  pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 AINCOME6           1       192
                           Allocation of Public Assistance Income in 1979
           0               Not allocated or N/A
           1               Allocated, pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck

 AINCOME7           1       193
                           Allocation of All Other Income in 1979
           0               Not allocated or N/A
           1               Allocated, pre-edit*
           2               Allocated, consistency edit*
           3               Allocated, hot deck



 *Not counted as an allocation in census publications (PC80-1-C)




This page last reviewed: Thursday, January 28, 2016
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