demographics_decennial_baseline_county
Census 2020 DHC: full enumeration race/ethnicity counts by county (A7). Tier A+. Race counts, shares, and diversity index are fully populated for all 3,222 counties; Connecticut's 9 planning regions are reallocated from the DHC's pre-2022 8-county FIPS via the legacy-county crosswalk (geo_basis='crosswalk_estimate').
tier acensus
overview
overview
Complete enumeration of all 3,213 US counties + DC. Decennial census is a full count, not a sample.
current vintage — 2020 (released May 2023)
history — Decennial from 1790; DHC format from 2010 forward
provenance
source & licensing
authority
U.S. Census Bureau
dataset
2020 Decennial Census Demographic and Housing Characteristics (DHC)
source url
license
Public domain (U.S. Federal Government work)
citation
U.S. Census Bureau. 2020 Census Demographic and Housing Characteristics File (DHC).
schema
fields
| name | type | definition |
|---|---|---|
| country_idkey | string | ISO alpha-2 country code (always 'US' for domestic tables).Part of primary key. |
| county_idkey | string | 5-character FIPS code identifying the county.Part of primary key. Joins dim.counties on county_id. |
| county_name | string | Human-readable county name corresponding to county_id. |
| geo_basis | string | Geography provenance flag: 'source' for rows at the DHC's native county geography; 'crosswalk_estimate' for Connecticut's 9 planning regions reallocated from the pre-2022 8-county FIPS via the population-weighted legacy-county crosswalk (us_dimension.crosswalk_legacy_county). |
| pct_aian_nh | float64 · percent (0–100) | Share of total county population that is American Indian and Alaska Native alone, non-Hispanic, computed as pop_aian_nh / total_population_2020 × 100. |
| pct_asian_nh | float64 · percent (0–100) | Share of total county population that is Asian alone, non-Hispanic, computed as pop_asian_nh / total_population_2020 × 100. |
| pct_black_nh | float64 · percent (0–100) | Share of total county population that is Black or African American alone, non-Hispanic, computed as pop_black_nh / total_population_2020 × 100. |
| pct_hispanic | float64 · percent (0–100) | Share of total county population that is Hispanic or Latino of any race, computed as pop_hispanic / total_population_2020 × 100. |
| pct_multiracial_nh | float64 · percent (0–100) | Share of total county population identifying as Two or More Races, non-Hispanic, computed as pop_multiracial_nh / total_population_2020 × 100. |
| pct_nhpi_nh | float64 · percent (0–100) | Share of total county population that is Native Hawaiian and Other Pacific Islander alone, non-Hispanic, computed as pop_nhpi_nh / total_population_2020 × 100. |
| pct_white_nh | float64 · percent (0–100) | Share of total county population that is White alone, non-Hispanic, computed as pop_white_nh / total_population_2020 × 100. |
| pop_aian_nh | int64 · count | Population identifying as American Indian and Alaska Native alone, non-Hispanic, from the 2020 Census DHC. Higher values indicate a larger non-Hispanic AIAN population. |
| pop_asian_nh | int64 · count | Population identifying as Asian alone, non-Hispanic, from the 2020 Census DHC. Higher values indicate a larger non-Hispanic Asian population. |
| pop_black_nh | int64 · count | Population identifying as Black or African American alone, non-Hispanic, from the 2020 Census DHC. Higher values indicate a larger non-Hispanic Black population. |
| pop_hispanic | int64 · count | Population identifying as Hispanic or Latino of any race, from the 2020 Census DHC. Higher values indicate a larger Hispanic/Latino population. |
| pop_multiracial_nh | int64 · count | Population identifying as Two or More Races, non-Hispanic, from the 2020 Census DHC. Higher values indicate a larger non-Hispanic multiracial population. |
| pop_nhpi_nh | int64 · count | Population identifying as Native Hawaiian and Other Pacific Islander alone, non-Hispanic, from the 2020 Census DHC. Higher values indicate a larger non-Hispanic NHPI population. |
| pop_other_nh | int64 · count | Population identifying as Some Other Race alone, non-Hispanic, from the 2020 Census DHC. Higher values indicate a larger non-Hispanic other-race population. |
| pop_white_nh | int64 · count | Population identifying as White alone, non-Hispanic, from the 2020 Census DHC. Higher values indicate a larger non-Hispanic White population. |
| racial_diversity_index | float64 · share (0–1) | Probability that two randomly selected residents belong to different race/ethnicity groups, computed as 1 − Σ(group share²) across the mutually exclusive race/ethnicity categories. Higher values indicate greater racial/ethnic diversity. |
| state_idkey | string | 2-character FIPS code identifying the state.Part of primary key. Joins dim.states on state_id. |
| total_population_2020 | int64 · count | Total resident population of the county from the 2020 Census Demographic and Housing Characteristics (DHC) full enumeration. |
relationships
joins
primary key
county_id, state_id, country_id
common joins
dim.geographies on county_id
demographics_population_county_year for time series
usage
how to use this table
method
Complete decennial enumeration with differential-privacy noise injection. Loaded from Decennial 2020 DHC.
do not use for
Annual change analysis; current-year estimates (use PEP); small-area racial counts where DP noise is material.
known issues
DHC introduces differential-privacy noise - small-area counts can shift across releases.
← previousus_demographics.demographics_age_sex_race_county_yearnext →us_demographics.demographics_education_county_year
last updated · Jul 7, 2026