Sources
Sources and data appendix
This page brings the report appendix into HTML so the site has a dedicated source and methodology reference for readers, researchers, and search engines.
About the Data Appendix
The Data Appendix provides detailed documentation of all data sources, variable definitions, and derived fields used throughout the tribal profiles.
It documents Census variable codes used in demographic tables, derived field definitions, broadband data source notes for Ookla and FCC data, and methodology for the June 2025 FCC Broadband Data Collection filing.
The appendix also describes the panel dataset and standalone FCC data files used to generate the report pages.
Census Variable Definitions
| Variable | Table | Description | Report Field |
|---|---|---|---|
| B01003_001E | B01003 | Total Population | Population |
| B01002_001E | B01002 | Median Age by Sex — Both sexes | Median Age |
| B01001_002E | B01001 | Sex by Age — Male | Male Population |
| B01001_026E | B01001 | Sex by Age — Female | Female Population |
| B11001_001E | B11001 | Household Type — Total households | Households |
| B25010_001E | B25010 | Avg. Household Size of Occupied Housing Units | Avg. Household Size |
| B19013_001E | B19013 | Median Household Income (in dollars) | Median Household Income |
| B19301_001E | B19301 | Per Capita Income (in dollars) | Per Capita Income |
| B17001_001E | B17001 | Poverty Status — Total (for whom determined) | Poverty Rate numerator / denominator |
| B17001_002E | B17001 | Poverty Status — Below poverty level | Poverty Rate numerator / denominator |
| B23025_002E | B23025 | Employment Status — In labor force (16+) | Unemployment Rate numerator / denominator |
| B23025_005E | B23025 | Employment Status — Unemployed | Unemployment Rate numerator / denominator |
| B15003_001E | B15003 | Educational Attainment — Total (pop. 25+) | HS diploma or higher / Bachelor’s or higher |
| B15003_017E | B15003 | Educational Attainment — High school diploma | HS diploma or higher |
| B15003_018E | B15003 | Educational Attainment — GED or equivalent | HS diploma or higher |
| B15003_021E | B15003 | Educational Attainment — Associate’s degree | HS diploma or higher |
| B15003_022E | B15003 | Educational Attainment — Bachelor’s degree | Bachelor’s or higher |
| B15003_023E | B15003 | Educational Attainment — Master’s degree | Bachelor’s or higher |
| B15003_024E | B15003 | Educational Attainment — Professional school degree | Bachelor’s or higher |
| B15003_025E | B15003 | Educational Attainment — Doctorate degree | Bachelor’s or higher |
Derived Fields
- Male / Female %: male population divided by total population; female population divided by total population.
- Population density: total population divided by land area in square miles from the Census TIGERweb ALAND field.
- Household density: total households divided by land area in square miles from the Census TIGERweb ALAND field.
- Poverty rate: population below poverty level divided by total population for whom poverty status is determined.
- Unemployment rate: unemployed population divided by population in the labor force.
- HS diploma or higher: sum of high school diploma through doctorate counts divided by total population age 25+.
- Bachelor’s or higher: sum of bachelor’s degree through doctorate counts divided by total population age 25+.
Notes
- Values of -666666666 returned by the Census API indicate suppressed data and are displayed as em dashes in the report.
- ACS 5-year estimates are based on a rolling five-year sample ending in the indicated year.
- AIANNHCE codes are the 4-digit Census geography identifiers used to join Census, FCC, geographic boundary, and website-summary data.
Broadband Data Sources
- Speed Trends (Ookla): quarterly mean download and upload throughput in Mbps from the Ookla Open Data Initiative, aggregated to AIANNH boundaries.
- Availability (FCC BDC): share of population with access at specified speed tiers from the FCC Broadband Data Collection.
- Adoption (FCC): fixed broadband subscribers as a share of households, including all households and low-income households.
FCC Broadband Data Collection — June 2025 Filing
- Provider Summary by Geography: one row per provider per tribal geography, used to count fixed and mobile providers and list provider names.
- Fixed Broadband Summary by Geography: residential coverage percentages by speed tier and technology type, plus broadband serviceable locations.
- Mobile Broadband Summary by Geography: area coverage percentages for 3G, 4G LTE, and 5G-NR plus total tribal land area.
- Provider List: maps FCC provider IDs to holding company names.
Tribal geography codes in FCC files use reservation and off-reservation trust land suffixes. TribalGeo aggregates those records under the shared base AIANNHCE code to match the report methodology.