The 2020 Census is comprised of the Redistricting (P.L. 94-171 Redistricting Data) and the Summary File 1 (SF1) data releases. These are both 100% counts of the US population and because of this have a more limited scope of questions. They are considered the official decentennial (occurring every ten years) census. A supplementary data set is the American Community Survey 2016-2020 (ACS 2020) which contains a richer demographic view of Americans. The ACS is not officially part of the census but has replaced the "Long Form" or SF3 that was historically part of the census. This is data that the USCB models from a longer questionnaire that is only sent to a subset of people (about 1 in 60 households annually).
What Data is Available in Each Data Set
- 2020 Redistricting - Public Law (P.L.) 94-171 requires the Census Bureau to provide only counts of the total population for a variety of geographic areas to be used for the redistricting process. In addition, other data items such as race, ethnicity, voting age and housing unit tallies are included in this data set.
- 2020 Summary File (SF1) - the 100-percent data counts with both demographic profiles, summary files of aggregated data, and reports. This has most of the same geographies as Redistricting but a much more robust data set and age breakouts.
- 2020 Block Data files – we expect that both the 2020 Redistricting and the 2020 Summary File include data down to the block level.
- 2020 American Community Survey (ACS) - while not officially part of the 2010 Census this data set replaces the "Long Form" or SF3 released in prior census years. It includes variables such as income, housing value, employment, ancestry, educational attainment etc. that are not available in either the Redistricting or Summary File 1 data sets.
Normally the US Census Bureau (USCB) would deliver the Redistricting data set to all states starting Feb. 18, 2021 and finishing by March 31, 2021. However, COVID-19 delayed Census operations significantly. They focused first on their constitutional obligation to deliver the state population counts for appointment to the President. This deadline was April 30, 2021. Then they switched to processing the necessary data to generate the redistricting counts. These are expected to be released for the whole US by Sept. 30, 2021.
The Summary File 1 will be released after that.