Tribal Self-Governance Health Care and Social Services Delivery Effectiveness Evaluation Feasibility Study: Tribal Population Data Report. Methods

03/07/2003

The construction of the Tribal Data Report required: 1) identification of each federally-recognized Tribe (and of individual Alaska Native Tribes that are members of an AN corporation); and 2) identification of national data sources that could provide data by Tribe (or Reservation) on relevant characteristics.

Federally-recognized Tribes

A complete list of all federally-recognized Tribes was obtained from the Federal Register (1). This list was then cross-referenced with Indian Health Service information to match Alaska Native Tribes to Alaska Native Corporations and with other inter-Tribal organizations that may hold compacts, contracts, or grants as a consortium.

Sources of Data

The data that were used to develop these tables were obtained from the following sources.

  1. The U.S. Census 2000 Summary Files - Information on population totals and population characteristics was extracted from the U.S. Census Summary Files 1 (SF 1) and 3 (SF 3). SF 1 contains data that was collected by the Census Bureau from all persons as part of the 2000 census; data are based on 100 percent of the population. In contrast, the data that comprise the SF 3 is based on a sample of people or housing units and have been weighted to generate estimates for the entire population; data for reservations with a small population may be less reliable than that for reservations having large populations. Because the SF 3 is a sample, data for some reservations cannot be provided due to the very small number of people sampled. Estimates derived from the SF 3, including estimates of educational attainment, poverty and disability rates, should be interpreted cautiously since for some Tribes the sample data represent fewer than 250 observations. Another consideration in interpreting data from either the SF 1 or the SF 3 is that all persons residing on Reservation lands are included in the estimates regardless of whether or not they are American Indian/Alaska Native.
  2. Reports from the Bureau of Indian Affairs (BIA) - The BIA report "1997 Labor Market Information On the Indian Labor Force" was used to extract a limited amount of data and specifically information on persons in the labor force who are living in poverty. Data from this BIA labor market report are compiled for federally recognized tribes.

Data Specification

The specification for each of the data elements contained in these tables and the source of information are listed below. Because Census 2000 data were based on the population of Reservation lands, it was necessary to manually assign Tribes to Reservations in order to produce Tribal-specific data estimates. The variables included in the Data Tables and their computations include:

Total Population

Counts of the total population residing on a Reservation were derived from the U.S. Census Summary File 1, which represents 100 percent of the census data. This figure includes persons of all races and ethnicities.

Total Persons, American Indian/Alaska Native, One Race

This figure, which was derived from U.S. Census Summary File 1, is the count of persons who resided on a reservation and indicated on the Census that they were American Indian or Alaska Native and were not of mixed race.

Total, American Indian/Alaska Native, One Race, %

This figure was computed as the proportion of all persons residing on a reservation and who indicated that they were American Indian or Alaska Native and were not of mixed race.

Total, American Indian/Alaska Native, One or More Race

Obtained from the Census Summary File 1, this figure is the count of persons on a reservation who indicated that they were American Indian or Alaska Native either alone or in combination with another race.

Total American Indian/Alaska Native, One or More Race, %

This computed figure represents the proportion of all persons on each reservation who indicated that they were American Indian or Alaska Native either alone and or in combination with another race.

Total Males

Counts of the total number of men - of all races and ages - residing on a reservation were obtained from the Census Summary File 1.

Males, %

The proportion of all persons residing on a reservation that were male was calculated from data in Summary File 1.

Total Age < 18

Counts of the total number of persons residing on a reservation who were under the age of 18 were obtained from the U.S. Census Summary File 1. This figure includes persons of all races and ethnicities.

Age < 18, %

The proportion of all persons residing on a reservation who were under the age of 18 was calculated from data in the 2000 Census Summary File 1.

Total Age 18-64

Counts of the total number of persons residing on a reservation who were adults between the ages of 18 and 64 were obtained from the U.S. Census Summary File 1. This figure includes persons of all races and ethnicities.

Total Age 18-64, %

The proportion of all persons residing on a reservation who were between the ages of 18 and 64 was calculated from data in the 2000 Census Summary File 1.

Total Age 65+

Counts of the total number of persons residing on a reservation who were adults aged 65 or older were obtained from the U.S. Census Summary File 1. This figure includes persons of all races and ethnicities.

Total Age 65+, %

The proportion of all persons residing on a reservation who were aged 65 or older was calculated from data in the 2000 Census Summary File 1.

High School Graduates, %

The proportion of persons aged 25 or over who were residing on a reservation and who graduated from high school or received a high school equivalency was calculated from data in the U.S. Census Summary File 3.

Poverty Rate, %

Derived from data in the U.S. Census Summary File 3, the poverty rate represents the proportion of all persons residing on a reservation with a family income below the poverty threshold.

Employed Living below Poverty, %

Obtained from data in the 1997 BIA Indian labor force market report, this data represents the total number of tribal members over the age of 16 who were employed and whose family income was below federal poverty guidelines.

Median Household Income in 1999

Data on median household income of people living on a reservation was obtained from the U.S. Census Summary File 3. This value represents the 50th percentile of the distribution of income for all households located on the reservation.

Disabled, %

The proportion of all persons residing on a reservation who were over the age of 5 and who had a disability was obtained from the Census Summary File 3. Persons were classified as disabled if they were over the age of 5 and had a sensory, physical, mental or self-care disability or they were over the age of 16 and had a condition that prevented them from going outside the home, or if they had a work disability.

Limitations of the Data

There are a number of important limitations of the data compiled for this report. These limitations include:

  1. The Census 2000 data contain self-reported information on race. Those who report that they are American Indian/Alaska Native may be members of Federally-recognized Tribes, members of state-recognized Tribes, or may not be affiliated with any Tribe on a formal basis. The Census 2000 Summary Files 1 and 3 provide data on people who reside on Reservation lands, and we have limited the data compilation to Reservations in order to focus on people who are most likely to be members of federally-recognized Tribes. (2)
  2. Because Census 2000 data are only available for Tribes that have formal Reservations, data cannot be reported for Tribes that do not have formal Reservations.
  3. Census 2000 data also are not available for geographic areas where fewer than 250 people reside, in order to protect the privacy of individuals.
  4. Due to the limitations cited in items #2 and #3 data are available in this report for only about two-thirds of Tribes. When Census 2000 data are released for individual Tribes, in December 2003, it may be possible to add data for Tribes that are missing in the table in this Report.
  5. Reservation-level data reported in the Census 2000 public use files include both AI/AN residents and non-AI/AN residents in the aggregate statistics on age distribution, education, income, and disability. To the extent that there are a significant number of non-AI/AN residents on a reservation, these variables may not closely represent age distribution, education, income, and disability rates of the AI/AN residents of the Tribe residing on the Reservation.
  6. BIA data on employment and poverty levels are constructed using methodologies that are different from those used by the U.S. Department of Labor and may not accurately reflect employment and poverty levels that are comparable to DOL estimates.

Despite these limitations, the data reported below provide some useful information on socio-economic and demographic characteristics of specific Tribes. The data, however, should be viewed as providing relative indications of differences among Tribes, rather than absolute and accurate data on each Tribe's characteristics.

Sources

Bureau of Indian Affairs. 1997 Labor Market Information on the Indian Labor Force: A National Report. Washington, D.C: Department of the Interior, n.d. Downloaded from www.bia.gov/bia/ (website is currently unavailable.)

U.S. Census Bureau. Census 2000 Summary File 1, Technical Documentation, 2001. http://www.census.gov/prod/cen2000/doc/sf1.pdf

U.S. Census Bureau. 2000 Census of Population and Housing, Summary File 3: Technical Documentation, 2002. http://www.census.gov/prod/cen2000/doc/sf3.pdf