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The U.S. Census and the Amazing Apportionment Machine

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Apportionment is the process of dividing the seats in the House of Representatives among the 50 states based on the population figures collected during the decennial census. The number of seats in the House has grown with the country. Congress sets the number in law and increased the number to 435 in 1913. The Constitution set the number of representatives at 65 from 1787 until the first Census of 1790, when the it was increased to 105 members.

But how does apportionment actually work? Through animation, the U.S. Census Bureau helps explain how the apportionment formula is used to ensure equal representation for all, just like the Founding Fathers planned.

Running time: 1:52

Interactive Population Map

Center of Population: How are the centers of population marked and can I go see them?

Center of Population: What trends or changes can we see?

Center of Population: What can we learn from these changes?


National Snapshot of Apportionment

National Snapshot of Apportionment

Sec. Locke Thanks the American Public

Sec. Locke Thanks the American Public

First Look at 2010 Census Data

First Look at 2010 Census Data

Dr. Blank Speaks about the Importance of the 2010 Census

Dr. Blank Speaks about the Importance of the 2010 Census