Scientific Data Documentation
Population Data From The 1990 Census
y90.mod.zip
SPECIAL NOTE
Some 1990 Census files have been modified for age and race
STF1A, SAS File 1990
CC36.SAS606.STF1A90.STATES) has NOT been modified.
STF1A, complete Count Pop & Housing Data, 1990
CC36.CENSUS.STF1A.XX : XX=State abbreviation)
has NOT been modified.
Pop. Data from the 1990 Census
(CC36.CENSUS90.MOD) has been modified
Population Data from the 1990 Census, SAS Files
CC36.SAS.CENSUS.STCTY90 (CTY90) has been modified
CC36.SAS.CENSUS.STCTY90 (STATES90) has been modified
ABSTRACT
General Information
AGE, SEX, RACE, AND HISPANIC ORIGIN INFORMATION FROM THE
1990 CENSUS: A COMPARISON OF CENSUS RESULTS WITH RESULTS WHERE
AGE AND RACE HAVE BEEN MODIFIED
The accompanying tables provide age, sex, race, and Hispanic
origin data from the 1990 census; as well as similar information
from a special census file where the age and race data have been
"modified" to meet the needs of many users of census data.
Essentially the race statistics were modified to be consistent
with the classification used in data sets other than the census,
while the age data were adjusted to correspond with the April 1,
1990 census date. These "modified" data are consistent
with the counts of the 1990 census as enumerated. More detailed
information for smaller geographic units should be released on
computer tapes and diskettes later this year by the Data Users
Services Division.
SEE SPECIAL NOTE
Race Modification
There were 9,804,847 "Other race" persons included in the
1990 census. These people were not included in one of the 15 racial
categories listed on the census form. Such "non-specified"
race persons are not found in data sources other than the census.
The existence of this group is also inconsistent with the race
categories defined by the Office of Management and Budget in OMB
Directive 15. In order to serve the needs of some portions of
the user community it is necessary to assign each of these
persons to a specified race.
After evaluating many alternatives, the following race assignment
rule was used: Assign each "Other race" person to the
specified race reported by a nearby person with an identical
response to the Hispanic origin question. The only alternative
specifications which yielded significantly different National
results were those where responses to the Hispanic origin
question were ignored during the assignment of race. This work
was done separately for each of the 449 district offices.
Background Information on the Race Assignment Rule
1. The specific Hispanic origin of each "Other race"
person in the 1990 census was taken into account when assigning
them to a specified race. This was considered appropriate
because over 95 percent of the "Other race" persons
were of Hispanic origin. Their origin response was used, whether
or not it had been allocated, in order to preserve the
race distribution within each type of origin. The specific
Hispanic origin responses were "not Spanish/Hispanic,
Mexican, Puerto Rican, Cuban, and other Spanish/Hispanic".
2. Virtually every person who reported both a specified race
and an origin was included in the "donor pool" of
eligible persons. The sole exception was the exclusion of
several non-specific American Indian codes from the donor pool.
These codes were: 548-Amerind White, 549--Amerind Black,
597 and 598--American Indian (general response), and
973--FOSDIC circle with no write-in response. These were
excluded because of evidence from the 1980 census that
misreporting of rtace was much higher in these codes than it
was in codes representing specific American Indian tribes.
Consistent with advisory committee recommendations, any person
assigned to the American Indian race was given code 973 rather than
a specific tribal code.
3. The assignment of a specified race was made on an
individual basis. That is, no effort was made to minimize
racial heterogeneity within households. Any such attempt
would have made it difficult to assign race in a manner
which approximated the specified-race distribution reported
by persons with the same Hispanic origin response.
4. The race, origin, or sex of some persons also changed as a
result of the assignment of a different age to them during
the application of the age modification procedures. Their
changed age sometimes caused the person to be allocated a
different relationship and/or sex which resulted in the
person receiving their race or origin from a different
person in the household (Since those items were allocated
according to hierarchy of relationships).
5. The results of the race modification procedures were
overridden in four counties where the American Indian
population grew by more than 100 percent and also became at
least one percentage point more of the county's population:
Adams County, Washington; Harmon County, Oklahoma; Clark
County, Idaho; and Washington County, Idaho. In each case
the persons were made White.
6. In most census allocation procedures, acceptable data from
eligible persons (donors) are far more common than are the
cases where the value is assigned to persons without the
characteristic (the donees). This means information from
any given donor is rarely used more than once. However,
such large donor-to-donee ratios were not usual here.
There were a number of occasions where those needing a
specified race outnumbered those who reported the same
origin as well as a specified race.
Special procedures were adopted to minimize the distortions
produced by such low ratios of donors to donees in some
cells of these matrices. The most important change was to
expand each cell of every allocation matrix to hold 64
values, rather than the 8 stored in most 1990 census
matrices. For each district office, the initial race data
were then obtained by running the actual census file and
storing up to the first 64 acceptable cases in each data
cell. If the district office did not have 64 cases the
remaining values were assumed to be White. After the
matrices were so "warmed", the program went back to the
beginning of the data and began the race assignments. The
actual race assignment was a random selection from the
unused values within each cell. If all 64 values had been
used, then assignment was random from among all 64 until
new acceptable cases were available. Used values in a cell
were replaced with acceptable data in reverse of the order
of use.
Age Modification
The following is a portion of the text of a user note which is
incorporated in 1990 census products:
"Age Reporting -- Review of detailed 1990 information indicated
that respondents tended to provide their age as of the date of
completion of the questionnaire, not their age as of April 1,
1990. In addition, there may have been a tendency for
respondents to round up their age if they were close to having a
birthday. It is likely that approximately 10 percent of persons
in most age groups are actually 1 year younger. For most single
years of age, the misstatements are largely offsetting. The
problem is most pronounced at age 0 because persons lost to age 1
may not have been fully offset by the inclusion of babies born
after April 1, 1990 and because there may have been more rounding
up to age 1 to avoid reporting age as 0 years. (Age in completed
months was not collected for infants under age 1.)
The reporting of age 1 year older than age on April 1, 1990 is
likely to have been greater in areas where the census data were
collected later in 1990."
About 95 percent of the population provided acceptable birth year
responses which were adjusted with the following procedures. The
age data for individuals in households were modified by adjusting
the reported birth year data by race and sex for each of the
1990 Census 49 district offices to correspond with the national
level quarterly distribution of births available from the
national Center for Health Statistics. The data for persons in
group quarters were adjusted on a state basis to minimize the
number of matrix cells with very small numbers. The central
assumption in this procedure is that there is no reason for the
residents of any subnational area to have a different quarter of
birth distribution from that found at the national level. It was
also assumed that there are no significant birth place-sex-race-
origin differences in annual birth distributions by quarter, that
all those born before 1920 have the same quarter of birth
distribution, and that mortality is not selective by quarter of
birth. Approximately 100 million persons have an age in this
modified file which is one year different from that they had in
the 1990 census.
The nodification procedure was done separately for each birth
year, by sex, for the White; Black; Asian or Pacific Islander;
and American Indian, Eskimo, or Aleut populations. For every
birth year the program was provided with the number of cases out
of 10,000 where the birth year plus the person's age should equal
1989 (most years that number was close to 7,500). These overall
control values were calculated from the available monthly birth
statistics for the 1920 to 1989 period. Earlier birth years were
each assumed to have the same seasonal pattern as was exhibited
by the unweighted average of the 1920-24 birth cohorts. Each
sex-race-origin cell was next randomly assigned a value of 0,
0.25, 0.5, or 0.75. Then, each time that birth year cell was
encountered, a test was made to see if that birth year plus the
person's age should equal 1989 or 1990. The choice of an age was
dependent on whether its acceptance moved the cell's actual
population distribution toward the control value distribution.
RECORD LAYOUT
Character Item Description
--------- -----------------
1-2 FIPS State Code
3-5 Fips County Code
6 Blank
Age = Under 1 year:
7-15 Hispanic Male: White
16-24 Hispanic Male: Black
25-33 Hispanic Male: American Indian, Eskimo, and Aleut
34-42 Hispanic Male: Asian and Pacific Islander
43-51 Hispanic Female: White
52-60 Hispanic Female: Black
61-69 Hispanic Female: American Indian, Eskimo, and Aleut
70-78 Hispanic Female: Asian and Pacific Islander
79-87 Not Hispanic Male: White
88-96 Not Hispanic Male: Black
97-105 Not Hispanic Male: American Indian, Eskimo, and Aleut
106-114 Not Hispanic Male: Asian and Pacific Islander
115-123 Not Hispanic Female: White
124-132 Not Hispanic Female: Black
133-141 Not Hispanic Female: American Indian, Eskimo, and Aleut
142-150 Not Hispanic Female: Asian and Pacific Islander
Age = 1 year:
151-294 Repeat Hispanic Origin, Sex, Race cells as above
Age = 2 years:
295-438 Repeat Hispanic Origin, Sex, Race cells as above
Age = 3 years:
439-582 Repeat Hispanic Origin, Sex, Race cells as above
.
. Repeat for single years of age
. (All data cells are 9 characters each)
.
Age = 98 years:
14119-14262 Repeat Hispanic Origin, Sex, Race cells as above
Age = 99 years:
14263-14406 Repeat Hispanic Origin, Sex, Race cells as above
Age = 100 years:
14407-14550 Repeat Hispanic Origin, Sex, Race cells as above
