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Facts for Features
CB10-FFSE.05 (Updated)
Dec. 23, 2010

*Special Edition*
2010 Census and Apportionment

The 2010 Census enumeration began last January in a remote corner of Alaska and in the months that followed, America stepped up and achieved a successful census. As mandated by the Constitution, the census counts every resident in the United States every 10 years to determine the number of seats each state receives in the U.S. House of Representatives. Beginning this month, the nation will see the first results from the 2010 Census as a new portrait of America begins to take shape.

A New Portrait of America, First 2010 Census Results

308,745,538

Official resident population of the United States on April 1, 2010.

9.7

Percentage increase of the nation's population from 2000 to 2010.

37,253,956

Population of California, the most populous state in the country on April 1, 2010. The least populous was Wyoming (563,626).

35.1

Percentage growth of Nevada's population from 2000 to 2010, the highest in the nation.

710,767

Average number of people each member of the U.S. House represents, as apportioned by the 2010 Census.

8

Number of states that gained congressional seats in 2010. They are Arizona, Florida, Georgia, Nevada, South Carolina, Texas, Utah, and Washington.

4

Number of congressional seats Texas gained, more than any other state.

10

Number of states that lost congressional seats in 2010. They are Illinois, Iowa, Louisiana, Massachusetts, Michigan, Missouri, New Jersey, New York, Ohio, and Pennsylvania.

32

Number of states that did not gain or lose a congressional seat in 2010.

Apportionment

435

Number of seats in the U.S. House of Representatives to be apportioned among the 50 states. Each state has at least one representative. Apportionment is the process of dividing the 435 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 it was increased to 105 members.

Every 10 years

Time frame in which an apportionment of representatives among the states must be carried out, as mandated by Article 1, Section 2 of the U.S. Constitution. The first census was conducted in 1790. The 2010 Census is the 23rd census in American history.

Apportionment Population

People living in the 50 states, including adults, children, citizens and noncitizens, are counted in the apportionment population. In the 2010 Census, the apportionment population also included U.S. Armed Forces personnel and federal civilian employees serving outside the United States (and their dependents living with them).

Residents of the District of Columbia, Puerto Rico and the U.S. Island Areas

Populations that are excluded from the apportionment population because they do not have voting seats in the U.S. House of Representatives. The District of Columbia, the U.S. Virgin Islands, Guam, American Samoa and the Commonwealth of the Northern Mariana Islands are all represented by delegates. Puerto Rico, however, is represented by a “resident commission,” a position created by Congress in 1946.

Dec. 31, 2010

Date by which the President must receive the 2010 Census apportionment counts for each state, as required by Title 13, U.S. Code. The date is mandated as nine months from Census Day, which was April 1, 2010.

One Week

Upon the opening of the new session of Congress, the time frame, according to Title 2, U.S. Code, by which the President must report to the U.S. House of Representatives the apportionment population counts for each state and the number of representatives to which each state is entitled.

15

Number of days, after receiving the apportionment population counts from the President, that the clerk of the House of Representatives has to inform each state governor of the number of representatives to which that state is entitled.

Method of Equal Proportions

Method used to calculate the apportionment as decided by Congress, in accordance with the provisions of Title 2, U.S. Code. Each state is assigned one seat. Then, the apportionment formula allocates the remaining 385 congressional seats one at a time among the 50 states until all 435 seats are assigned. You can also learn more about apportionment through the video The Amazing Apportionment Machine on our YouTube channel: <http://www.youtube.com/watch?v=RUCnb5_HZc0>.

1940 Census

Census that the method of equal proportions was first used. The formula has been used in every census since, as directed by Congress, to apportion the U.S. House of Representatives.

2013

Year the reapportioned Congress, according to 2010 Census data, will first convene. It will be the 113th Congress.

Apportionment vs. redistricting

Apportionment is the process of determining the number of seats for each state in the U.S. House of Representatives based on the decennial census. Redistricting is the process of revising the geographic boundaries within a state from which people elect their representatives to the U.S. House of Representatives, state legislature, county or city council, school board, etc.

April 1, 2011

Date by which all states must receive redistricting data, in accordance with Public Law 94-171.

2010 Census

10

Number of questions on the 2010 Census form, one of the shortest in U.S. history.

134 million

Approximate number of total housing units in the U.S. contacted for the 2010 Census, either by mail or in person, to collect a form or determine if vacant.

74

Percentage of households that returned a 2010 Census form by mail, matching the mail participation rate achieved during the 2000 Census.

22

Number of states that, in 2010, met or exceeded their 2000 Census mail participation rate. The District of Columbia, Puerto Rico, 1,553 counties, and 278 cities and townships of 50,000 or more, also met or exceeded their rates.

$85 million

Estimated amount of taxpayer money the Census Bureau saved for each percentage point increase in the 2010 Census mail-back response rate. The Census Bureau saved money by not having to go door to door to count households that did not return the 2010 Census questionnaire by mail.

$1.87 billion

Amount of savings on operational costs returned, by the Census Bureau, to the U.S. Treasury. The savings were a result of great participation and cooperation by the public, efficient operations, and the non-use of contingency funds.

More than $400 billion

Amount in federal funds distributed each year to states and communities based in part on census population data.

1.4 million

The number of people hired for the 2010 Census in fiscal years 2009 and 2010.

585,000

Approximate number of positions hired for the door-to-door follow-up phase in 2010.

For life

The length of time a census worker is sworn to protect the confidentiality of census information.

257,000

Number of partner organizations that helped the Census Bureau spread the message out about the importance of the 2010 Census and mailing back the questionnaire.

2000 Census

281,421,906

Official resident population of the United States on April 1, 2000.

13.2

Percentage increase of the nation's population from 1990 to 2000.

33,871,648

Population of California, the most populous state in the country on April 1, 2000. The least populous was Wyoming (493,782).

66.3

Percentage growth of Nevada's population from 1990 to 2000, the highest in the nation.

647,000

Approximate number of people each member of the U.S. House represents, on average, as apportioned by the 2000 Census.

4

Number of states that gained two congressional seats in 2000. They were Arizona, Florida, Georgia and Texas.

2

Number of states that lost two congressional seats in 2000. They were New York and Pennsylvania.

32

Number of states that did not gain or lose a congressional seat in 2000.

For more information, please visit:
http://2010.census.gov/2010census/data/

Watch the video The Amazing Apportionment Machine on our YouTube channel:
http://www.youtube.com/watch?v=RUCnb5_HZc0

For historical perspective on Congressional Apportionment, please visit:
http://www.census.gov/population/apportionment/about/history.html

For a census brief about apportionment from the 2000 Census, please visit:
www.census.gov/prod/2001pubs/c2kbr01-7.pdf

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Source: U.S. Census Bureau | Public Information Office | PIO@census.gov | Last Revised: September 01, 2014