Apportionment Scenario Planner

What happens to congressional apportionment if the Census count changes?

Work in progress. This tool is in active development. Data, methodology, and interface are subject to change. Results are estimates based on ACS proportions applied to decennial counts and should not be cited as definitive.

Foreign-Born Non-Response

Non-Citizen Exclusion

Excludes non-citizens from the count entirely (not just non-response).

Race/Ethnicity Non-Response

Age/Sex Non-Response

Applies on top of other scenarios without double-counting.

Data: 2020 Decennial Census, 2019 ACS 1-Year

Method: Huntington-Hill (current U.S. apportionment method)

  • Map
  • Results Table
  • Seat Changes