Data Dictionary: Census 2000
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Survey: Census 2000
Data Source: U.S. Census Bureau
Table: PCT12B. Sex By Age (Black Alone) [209]
Universe: People who are Black or African American alone
Table Details
PCT12B. Sex By Age (Black Alone)
Universe: People who are Black or African American alone
Variable Label
PCT012B001
PCT012B002
PCT012B003
PCT012B004
PCT012B005
PCT012B006
PCT012B007
PCT012B008
PCT012B009
PCT012B010
PCT012B011
PCT012B012
PCT012B013
PCT012B014
PCT012B015
PCT012B016
PCT012B017
PCT012B018
PCT012B019
PCT012B020
PCT012B021
PCT012B022
PCT012B023
PCT012B024
PCT012B025
PCT012B026
PCT012B027
PCT012B028
PCT012B029
PCT012B030
PCT012B031
PCT012B032
PCT012B033
PCT012B034
PCT012B035
PCT012B036
PCT012B037
PCT012B038
PCT012B039
PCT012B040
PCT012B041
PCT012B042
PCT012B043
PCT012B044
PCT012B045
PCT012B046
PCT012B047
PCT012B048
PCT012B049
PCT012B050
PCT012B051
PCT012B052
PCT012B053
PCT012B054
PCT012B055
PCT012B056
PCT012B057
PCT012B058
PCT012B059
PCT012B060
PCT012B061
PCT012B062
PCT012B063
PCT012B064
PCT012B065
PCT012B066
PCT012B067
PCT012B068
PCT012B069
PCT012B070
PCT012B071
PCT012B072
PCT012B073
PCT012B074
PCT012B075
PCT012B076
PCT012B077
PCT012B078
PCT012B079
PCT012B080
PCT012B081
PCT012B082
PCT012B083
PCT012B084
PCT012B085
PCT012B086
PCT012B087
PCT012B088
PCT012B089
PCT012B090
PCT012B091
PCT012B092
PCT012B093
PCT012B094
PCT012B095
PCT012B096
PCT012B097
PCT012B098
PCT012B099
PCT012B100
PCT012B101
PCT012B102
PCT012B103
PCT012B104
PCT012B105
PCT012B106
PCT012B107
PCT012B108
PCT012B109
PCT012B110
PCT012B111
PCT012B112
PCT012B113
PCT012B114
PCT012B115
PCT012B116
PCT012B117
PCT012B118
PCT012B119
PCT012B120
PCT012B121
PCT012B122
PCT012B123
PCT012B124
PCT012B125
PCT012B126
PCT012B127
PCT012B128
PCT012B129
PCT012B130
PCT012B131
PCT012B132
PCT012B133
PCT012B134
PCT012B135
PCT012B136
PCT012B137
PCT012B138
PCT012B139
PCT012B140
PCT012B141
PCT012B142
PCT012B143
PCT012B144
PCT012B145
PCT012B146
PCT012B147
PCT012B148
PCT012B149
PCT012B150
PCT012B151
PCT012B152
PCT012B153
PCT012B154
PCT012B155
PCT012B156
PCT012B157
PCT012B158
PCT012B159
PCT012B160
PCT012B161
PCT012B162
PCT012B163
PCT012B164
PCT012B165
PCT012B166
PCT012B167
PCT012B168
PCT012B169
PCT012B170
PCT012B171
PCT012B172
PCT012B173
PCT012B174
PCT012B175
PCT012B176
PCT012B177
PCT012B178
PCT012B179
PCT012B180
PCT012B181
PCT012B182
PCT012B183
PCT012B184
PCT012B185
PCT012B186
PCT012B187
PCT012B188
PCT012B189
PCT012B190
PCT012B191
PCT012B192
PCT012B193
PCT012B194
PCT012B195
PCT012B196
PCT012B197
PCT012B198
PCT012B199
PCT012B200
PCT012B201
PCT012B202
PCT012B203
PCT012B204
PCT012B205
PCT012B206
PCT012B207
PCT012B208
PCT012B209
Relevant Documentation:
Excerpt from: Social Explorer, U.S. Census Bureau; 2000 Census of Population and Housing, Summary File 1: Technical Documentation, 2001.
 
Sex
The data on sex were derived from answers to a question that was asked of all people. Individuals were asked to mark either "male" or "female" to indicate their sex. For most cases in which sex was not reported, it was determined by the appropriate entry from the persons given (i.e., first) name and household relationship. Otherwise, sex was imputed according to the relationship to the householder and the age of the person. (For more information on imputation, see "Accuracy of the Data.")

Sex ratio
A measure derived by dividing the total number of males by the total number of females and multiplying by 100.

Comparability
A question on the sex of individuals has been asked of the total population in every census.
For more information on sex, please telephone 301-457-2378.

Excerpt from: Social Explorer, U.S. Census Bureau; 2000 Census of Population and Housing, Summary File 1: Technical Documentation, 2001.
 
Age
The data on age were derived from answers to a question that was asked of all people. The age classification is based on the age of the person in complete years as of April 1, 2000. The age of the person was usually derived from their date of birth information. Their reported age was used only when date of birth information was unavailable.

Data on age are used to determine the applicability of some of the sample questions for a person and to classify other characteristics in census tabulations. Age data are needed to interpret most social and economic characteristics used to plan and examine many programs and policies.

Median age
This measure divides the age distribution into two equal parts: one-half of the cases falling below the median value and one-half above the value. Median age is computed on the basis of a single year of age distribution.

Limitation of the data
The most general limitation for many decades has been the tendency of people to overreport ages or years of birth that end in zero or five. This phenomenon is called "age heaping." In addition, the counts in the 1970 and 1980 censuses for people 100 years old and over were substantially overstated. So also were the counts of people aged 69 in 1970 and aged 79 in 1980. Improvements have been made since then in the questionnaire design, and in the allocation procedures which have further minimized these problems. The count of people aged 89 in the 1990 census was not overstated.

Review of detailed 1990 census information indicated that respondents tended to provide their age as of the date they completed the questionnaire, not their age as of April 1, 1990. One reason this happened was that respondents were not specifically instructed to provide their age as of April 1, 1990. Another reason was that data collection efforts continued well past the census date. In addition, there may have been a tendency for respondents to round their age up if they were close to having a birthday. It is likely that approximately 10 percent of people in most age groups were actually one year younger. For most single years of age, the misstatements were largely offsetting. The problem is most pronounced at age zero because people lost to age one probably were not fully offset by the inclusion of babies born after April 1, 1990. Also, there may have been more rounding up to age one to avoid reporting age as zero years. (Age in complete months was not collected for infants under age one.)

The reporting of age one year older than true age on April 1, 1990, is likely to have been greater in areas where the census data were collected later in calendar year 1990. The magnitude of this problem was much less in the 1960, 1970, and 1980 censuses where age was typically derived from respondent data on year of birth and quarter of birth.

These shortcomings were minimized in Census 2000 because age was usually calculated from exact date of birth and because respondents were specifically asked to provide their age as of April 1, 2000. (For more information on the design of the age question, see the section below that discusses "Comparability.")

Comparability
Age data have been collected in every census. For the first time since 1950, the 1990 data were not available by quarter year of age. This change was made so that coded information could be obtained for both age and year of birth. In 2000, each individual has both an age and an exact date of birth. In each census since 1940, the age of a person was assigned when it was not reported. In censuses before 1940, with the exception of 1880, people of unknown age were shown as a separate category. Since 1960, assignment of unknown age has been performed by a general procedure described as "imputation." The specific procedures for imputing age have been different in each census. (For more information on imputation, see "Accuracy of the Data.")
For more information on age, please telephone 301-457-2428.

Excerpt from: Social Explorer, U.S. Census Bureau; 2000 Census of Population and Housing, Summary File 1: Technical Documentation, 2001.
 
Black or African American
A person having origins in any of the Black racial groups of Africa. It includes people who indicate their race as Black, African Am., or Negro, or provide written entries such as African American, Afro American, Kenyan, Nigerian, or Haitian.