Data Dictionary: Census 2000
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Survey: Census 2000
Data Source: U.S. Census Bureau
Table: PCT12C. Sex By Age (AIAN Alone) [209]
Universe: People who are American Indian and Alaska Native alone
Table Details
PCT12C. Sex By Age (AIAN Alone)
Universe: People who are American Indian and Alaska Native alone
Variable Label
PCT012C001
PCT012C002
PCT012C003
PCT012C004
PCT012C005
PCT012C006
PCT012C007
PCT012C008
PCT012C009
PCT012C010
PCT012C011
PCT012C012
PCT012C013
PCT012C014
PCT012C015
PCT012C016
PCT012C017
PCT012C018
PCT012C019
PCT012C020
PCT012C021
PCT012C022
PCT012C023
PCT012C024
PCT012C025
PCT012C026
PCT012C027
PCT012C028
PCT012C029
PCT012C030
PCT012C031
PCT012C032
PCT012C033
PCT012C034
PCT012C035
PCT012C036
PCT012C037
PCT012C038
PCT012C039
PCT012C040
PCT012C041
PCT012C042
PCT012C043
PCT012C044
PCT012C045
PCT012C046
PCT012C047
PCT012C048
PCT012C049
PCT012C050
PCT012C051
PCT012C052
PCT012C053
PCT012C054
PCT012C055
PCT012C056
PCT012C057
PCT012C058
PCT012C059
PCT012C060
PCT012C061
PCT012C062
PCT012C063
PCT012C064
PCT012C065
PCT012C066
PCT012C067
PCT012C068
PCT012C069
PCT012C070
PCT012C071
PCT012C072
PCT012C073
PCT012C074
PCT012C075
PCT012C076
PCT012C077
PCT012C078
PCT012C079
PCT012C080
PCT012C081
PCT012C082
PCT012C083
PCT012C084
PCT012C085
PCT012C086
PCT012C087
PCT012C088
PCT012C089
PCT012C090
PCT012C091
PCT012C092
PCT012C093
PCT012C094
PCT012C095
PCT012C096
PCT012C097
PCT012C098
PCT012C099
PCT012C100
PCT012C101
PCT012C102
PCT012C103
PCT012C104
PCT012C105
PCT012C106
PCT012C107
PCT012C108
PCT012C109
PCT012C110
PCT012C111
PCT012C112
PCT012C113
PCT012C114
PCT012C115
PCT012C116
PCT012C117
PCT012C118
PCT012C119
PCT012C120
PCT012C121
PCT012C122
PCT012C123
PCT012C124
PCT012C125
PCT012C126
PCT012C127
PCT012C128
PCT012C129
PCT012C130
PCT012C131
PCT012C132
PCT012C133
PCT012C134
PCT012C135
PCT012C136
PCT012C137
PCT012C138
PCT012C139
PCT012C140
PCT012C141
PCT012C142
PCT012C143
PCT012C144
PCT012C145
PCT012C146
PCT012C147
PCT012C148
PCT012C149
PCT012C150
PCT012C151
PCT012C152
PCT012C153
PCT012C154
PCT012C155
PCT012C156
PCT012C157
PCT012C158
PCT012C159
PCT012C160
PCT012C161
PCT012C162
PCT012C163
PCT012C164
PCT012C165
PCT012C166
PCT012C167
PCT012C168
PCT012C169
PCT012C170
PCT012C171
PCT012C172
PCT012C173
PCT012C174
PCT012C175
PCT012C176
PCT012C177
PCT012C178
PCT012C179
PCT012C180
PCT012C181
PCT012C182
PCT012C183
PCT012C184
PCT012C185
PCT012C186
PCT012C187
PCT012C188
PCT012C189
PCT012C190
PCT012C191
PCT012C192
PCT012C193
PCT012C194
PCT012C195
PCT012C196
PCT012C197
PCT012C198
PCT012C199
PCT012C200
PCT012C201
PCT012C202
PCT012C203
PCT012C204
PCT012C205
PCT012C206
PCT012C207
PCT012C208
PCT012C209
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.
 
American Indian or Alaska Native
A person having origins in any of the original peoples of North and South America (including Central America) and who maintain tribal affiliation or community attachment. It includes people who classified themselves as described below.

American Indian
Includes people who indicated their race as "American Indian," entered the name of an Indian tribe, or reported such entries as Canadian Indian, French American Indian, or Spanish-American Indian.

American Indian tribe
Respondents who identified themselves as American Indian were asked to report their enrolled or principal tribe. Therefore, tribal data in tabulations reflect the written entries reported on the questionnaires. Some of the entries (for example, Iroquois, Sioux, Colorado River, and Flathead) represent nations or reservations. The information on tribe is based on self identification and therefore does not reflect any designation of federally or state-recognized tribe. Information on American Indian tribes is presented in summary files. The information for Census 2000 is derived from the American Indian Tribal Classification List for the 1990 census that was updated based on a December 1997 Federal Register Notice, entitled "Indian Entities Recognized and Eligible to Receive Service From the United States Bureau of Indian Affairs," Department of the Interior, Bureau of Indian Affairs, issued by the Office of Management and Budget.

Alaska Native
Includes written responses of Eskimos, Aleuts, and Alaska Indians as well as entries such as Arctic Slope, Inupiat, Yupik, Alutiiq, Egegik, and Pribilovian. The Alaska tribes are the Alaskan Athabascan, Tlingit, and Haida. The information for Census 2000 is based on the American Indian Tribal Classification List for the 1990 census, which was expanded to list the individual Alaska Native Villages when provided as a written response for race.