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The Constitutional basis for conducting the decennial census is to reapportion the U.S. House of Representatives. Apportionment is the process of distributing the 435 memberships, or seats, in the U.S. House of Representatives among the 50 states.
Redistricting Data Program
Public Law 94-171 requires the Census to provide state legislatures with the small area census population tabulations necessary for legislative redistricting.
2020 Census Data Quality
We check the quality of our work every step of the way. When we release data, we make sure they meet our quality standards.
Historical Apportionment Data Map (Interactive)
This interactive tool enables users to view more than 10 decades of apportionment and population data.