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Congressional Apportionment


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Article

  Congressional Apportionment

downThe average size of a congressional district will rise.
downTwelve seats will shift from one state to another.
downShifts in congressional representation reflect regional trends in population
downFor more information

 
  The Constitutional basis for conducting the decennial census of population is to reapportion the U.S. House of Representatives. Apportionment is the process of dividing the 435 memberships, or seats, in the U.S. House of Representatives among the 50 states. With the exception of the 1920 Census, an apportionment has been made by the Congress on the basis of each decennial census from 1790 to 2010.

The apportionment population for 2010 consists of the resident population of the 50 states plus overseas federal employees (military and civilian) and their dependents living with them, who were included in their home states. The population of the District of Columbia is excluded from the apportionment population because it does not have any voting seats in the U.S. House of Representatives. The 2010 Census apportionment population was 309,183,463.

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  The average size of a congressional district will rise.
  The number of representatives or seats in the U.S. House of Representatives has remained constant at 435 since 1911, except for a temporary increase to 437 at the time of admission of Alaska and Hawaii as states in 1959. However, the apportionment based on the 1960 Census, which took effect for the election in 1962, reverted to 435 seats.

The average size of a congressional district based on the 2010 Census apportionment population will be 710,767, more than triple the average district size 100 years ago, and 63,815 more than the average size based on the 2000 Census. Based on the 2010 Census apportionment, the state with the largest average district size will be Montana and the state with the smallest average district size will be Rhode Island.

State 2010
Apportionment
Population
Number of
Representatives
 2010   2000    1910
         
Total 309,183,463 435 435 435
Alabama 4,802,982 7 7 10
Alaska 721,523 1 1 0
Arizona 6,412,700 9 8 1
Arkansas 2,926,229 4 4 7
California 37,341,989 53 53 11
Colorado 5,044,930 7 7 4
Connecticut              3,581,628 5 5 5
Delaware 900,877 1 1 1
Florida 18,900,773 27 25 4
         
Georgia 9,727,566 14 13 12
Hawaii 1,366,862 2 2 0
Idaho 1,573,499 2 2 2
Illinois 12,864,380 18 19 27
Indiana 6,501,582 9 9 13
Iowa 3,053,787 4 5 11
Kansas 2,863,813 4 4 8
Kentucky 4,350,606 6 6 11
Louisiana 4,553,962 6 7 8
Maine 1,333,074 2 2 4
         
Maryland 5,789,929 8 8 6
Massachusetts 6,559,644 9 10 16
Michigan 9,911,626 14 15 13
Minnesota 5,314,879 8 8 10
Mississippi 2,978,240 4 4 8
Missouri 6,011,478 8 9 16
Montana 994,416 1 1 2
Nebraska 1,831,825 3 3 6
Nevada 2,709,432 4 3 1
New Hampshire 1,321,445 2 2 2
New Jersey 8,807,501 12 13 12
New Mexico 2,067,273 3 3 1
New York 19,421,055 27 29 43
North Carolina 9,565,781 13 13 10
North Dakota 675,905 1 1 3
Ohio 11,568,495 16 18 22
Oklahoma 3,764,882 5 5 8
Oregon 3,848,606 5 5 3
Pennsylvania 12,734,905 18 19 36
Rhode Island 1,055,247 2 2 3
         
South Carolina 4,645,975 7 6 7
South Dakota 819,761 1 1 3
Tennessee 6,375,431 9 9 10
Texas 25,268,418 36 32 18
Utah 2,770,765 4 3 2
Vermont 630,337 1 1 2
Virginia 8,037,736 11 11 10
Washington 6,753,369 10 9 5
West Virginia 1,859,815 3 3 6
Wisconsin 5,698,230 8 8 11
Wyoming 568,300 1 1 1
Table 1: Apportionment Based on the 2010 Census and Apportionment of the U.S. House of Representatives 2010, 2000, and 1910
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  Twelve seats in the U.S. House of Representatives will shift from one state to another.
  As a result of the apportionment based on the 2010 Census, 12 seats in the U.S. House of Representatives will shift among 18 states. Eight states will have more representatives in the 113th Congress, which convened in January 2013, and ten states will have fewer representative.

Among the eight states gaining seats, Texas will gain four seats and Florida will gain two seats. The other six states (Arizona, Georgia, Nevada, South Carolina, Utah, and Washington) will each gain one seat. Of the ten states losing seats, two states, New York and Ohio, will each lose two seats. The other eight states (Illinois, Iowa, Louisiana, Massachusetts, Michigan, Missouri, New Jersey, and Pennsylvania) will each lose one seat.

Change in the Number of
U.S. Representatives by State - 2010
State Gain State Loss
Total 12 Total 12
Texas 4 New York 2
Florida 2 Ohio 2
Arizona 1 Illinois 1
Georgia 1 Iowa 1
Nevada 1 Louisiana 1
South Carolina 1 Massachusetts 1
Utah 1 Michigan 1
Washington 1 Missouri 1
    New Jersey 1
    Pennsylvania 1
Table 2: Change in the Number of U.S. Representatives by state 2010
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  Shifts in congressional representation reflect regional trends in population.
  The regional patterns of change in congressional representation between 2000 and 2010 reflect the nation's continuing shift in population from the Northeast and Midwest to the South and West.

Based on the 2010 Census apportionment, the net increase of seven seats in the South reflected a gain of eight seats across four states and a loss of one seat. The West gained four seats and lost none. The Northeast lost five seats and gained none. The Midwest lost six seats and gained none.

  Figure 1: Regional shifts in congressional representation based on the 2010 census

Figure 1: Regional shifts in congressional representation based on the 2010 census

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  For more information
  For more information on apportionment for both the 2010 and 2000 censuses, visit the U.S. Census Bureau's Internet site. Other data from the 2010 Census are also available.
Adapted from Kristin D. Burnett, U.S. Census Bureau, Congressional Apportionment in 2010 Census Briefs.
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