2020 Redistricting Data Files – ALARM Project (original) (raw)

AK AL AR AZ CA CO CT DE FL GA HI IA ID IL IN KS KY LA MA MD ME MI MN MO MS MT NC ND NE NH NJ NM NV NY OH OK OR PA RI SC SD TN TX UT VA VT WA WI WV WY DC USA

The ALARM Project is glad to provide precinct-level demographic and election data from the 2020 decennial census and the Voting and Election Science Team which have been tidied and joined together using 2020 precinct boundaries. Where 2020 precinct boundaries are not available, Census block-level data is provided instead, and where no VEST data is available, only demographic information is provided. Code to generate the data from these sources is included; the entire workflow is open-source and reproducible.

Getting the data

Download individual states’ data below, or download a ZIP of all the data here. Our repository also contains more detailed data, as well as code and instructions for programmatic downloading, adding shapefile geometries, and other use cases.

Please make sure to cite the Voting and Election Science Team and the U.S. Census Bureau. Consult the license for information on modifying and sharing the data and/or code.

2020 state data

Using the data

Data Format

Each data table contains several identification columns, a set of census-derived demographic columns, and a set of VEST-derived election columns.

GEOID20 is the unique identifier for a precinct or Census block. The state and county of the precinct or block are also provided.
Census variables are prefixed with pop_ or vap_, depending on whether they are for the entire population or the voting-age population. Suffixes refer to racial and ethnic categories, as follows:
- _hisp: Hispanic or Latino (of any race)
- _white: White alone, not Hispanic or Latino
- _black: Black or African American alone, not Hispanic or Latino
- _aian: American Indian and Alaska Native alone, not Hispanic or Latino
- _asian: Asian alone, not Hispanic or Latino
- _nhpi: Native Hawaiian and Other Pacific Islander alone, not Hispanic or Latino
- _other: Some Other Race alone, not Hispanic or Latino
- _two: Population of two or more races, not Hispanic or Latino
Election variables consist of average vote counts for Democratic and Republican candidates. The adv_## and arv_## columns report the average vote count in the ## election, across all statewide races contested by both parties. The ndv and nrv columns further average the vote counts across all available election years. For specific statewide races, you may download the files in vest-2020/ and join them to the data using the GEOID20 column.

More Tools

For redistricting and voting rights analysis, we recommend the redist package.
For pre-processing and tidying data for redistricting analysis, we recommend the geomander package.
For more custom tabulations of the 2020 census data, we recommend the PL94171 package.
For general-purpose census data processing, we recommend the censable package.
For alternate data unaffected by Census differential privacy, you may want to consider FCC block-level estimates, available using the blockpop package.

Technical notes

To produce election data using 2020 precinct boundaries, election results were projected down to the 2010 block level using voting-age population as weights. Results for 2020 blocks were then estimated using 2010 blocks and the land-use-based crosswalk files from VEST. Finally, 2020 blocks were aggregated to 2020 precincts using the Census’ 2020 block assignment files.

2010 Data Addendum

If you are looking for a similar construction for 2010 data, please see here.

Citation

BibTeX citation:

@online{t._kenny2021,
  author = {T. Kenny, Christopher and McCartan, Cory},
  title = {2020 {Redistricting} {Data} {Files}},
  date = {2021-08-10},
  url = {https://alarm-redist.github.io/posts/2021-08-10-census-2020/},
  langid = {en}
}

For attribution, please cite this work as:

T. Kenny, Christopher, and Cory McCartan. 2021. “2020 Redistricting Data Files.” August 10, 2021. https://alarm-redist.github.io/posts/2021-08-10-census-2020/.