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Congressional Apportionment

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Frequently Asked Questions

  1. What is apportionment?
  2. Who is included in the apportionment population counts?
  3. Do the apportionment population counts include Americans overseas?
  4. What is the source of the overseas population counts?
  5. Are the overseas population counts used for redistricting?
  6. Which overseas groups were assigned to a home state for purposes of apportionment?
  7. On what basis are the components of the apportionment population counted?
  8. Who is excluded in the apportionment population counts?
  9. Why isn't the population of the District of Columbia included in the apportionment population counts?
  10. Why aren't the populations of Puerto Rico and other U.S. Island Areas included in the apportionment population counts?
  11. How is the apportionment calculated?
  12. Can the number of members/seats in the U.S. House of Representatives be increased?
  13. What is the mandate for conducting the apportionment?
  14. What is the average population per representative based on the 2010 Census apportionment?
  15. When are the apportionment population counts given to the President? To the Congress? To the states?
  16. Are undocumented residents (aliens) in the 50 states included in the apportionment population counts?
  17. Are children under 18 years old included in the apportionment population counts since they cannot vote?
  18. When will the apportionment population counts be released to the public? Will they be posted on the Internet?
  19. In past censuses, where have apportionment population counts been included in the data products?
  20. What is the difference between apportionment and redistricting?

What is apportionment?  back to top

Apportionment is the process of dividing the 435 memberships, or seats, in the U.S. House of Representatives among the 50 states.


Who is included in the apportionment population counts?  back to top

The apportionment calculation is based upon the total resident population (citizens and non-citizens) of the 50 states. In the 2010 Census, the apportionment population also includes U.S. Armed Forces personnel and federal civilian employees stationed outside the United States (and their dependents living with them) that can be allocated, based on administrative records, back to a home state. This is the same procedure used in 2000.


Do the apportionment population counts include Americans overseas?  back to top

Yes, the apportionment counts include those overseas federal employees (military and civilian) and their dependents living with them that can be allocated back to a home state. Included in these counts are members of the U.S. Armed Forces on military vessels assigned to a home port in a foreign country and their dependents overseas living in port near them. Private U.S. citizens living abroad, who are not employed by the Federal government are not included in the overseas counts for apportionment.


What is the source of the overseas population counts?  back to top

Overseas counts by home state were provided by the employing federal departments and agencies from their administrative records.


Are the overseas population counts used for redistricting?  back to top

No, the overseas counts are used solely for reapportioning seats in the U.S. House of Representatives. The home state data for the overseas population do not meet the substate geographical precision required to conduct redistricting (i.e., blocks).


Which overseas groups were assigned to a home state for purposes of apportionment?  back to top

Home state could be allocated for overseas U.S. Armed Forces and their dependents living with them and most overseas federal civilian employees and their associated dependents, except those overseas civilian employees and dependents of the Department of Defense (DOD). Home state information was not available for a number of overseas DOD civilian employees, as there is no DOD requirement for them to report this information.


On what basis are the components of the apportionment population counted?  back to top

People who are residents of the United States, which has always been the largest component of the apportionment population base, are to be counted at their usual residence. This is the place where they live and sleep most of the time (most of the week, month, or year). The other component of the apportionment population, overseas federal employees (military and civilian) and their dependents, is allocated back to the home state they report. These data are provided to the Census Bureau by the employing federal departments and agencies from their administrative records.


Who is excluded in the apportionment population counts?  back to top

The populations of the District of Columbia, Puerto Rico and the U.S. Island Areas are excluded from the apportionment population because they do not have voting seats in the U.S. House of Representatives.


Why isn't the population of the District of Columbia included in the apportionment population counts?  back to top

The population of the District of Columbia is not included in the apportionment counts because it does not have any voting seats in the U.S. House of Representatives.


Why aren't the populations of Puerto Rico and other U.S. Island Areas included in the apportionment population counts?  back to top

The populations of Puerto Rico and other U.S. Island Areas are not included in the apportionment counts because they do not have any voting seats in the U.S. House of Representatives.


How is the apportionment calculated?  back to top

The apportionment for the 2010 Census was calculated using the method of equal proportions, according to the provisions of Title 2, U.S. Code. Congress decides the method used to calculate the apportionment. This method has been used in every census since the 1940 census. The method computes "priority values" based on each state's apportionment population. For more details, see How it's Calculated


Can the number of members/seats in the U.S. House of Representatives be increased?  back to top

Yes, the number of House seats can be increased by legislation enacted by Congress. However, the number of House seats 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 just prior to the apportionment in 1960.


What is the mandate for conducting the apportionment?  back to top

Article I, Section 2 of the U.S. Constitution mandates that an apportionment of representatives among the states be carried out within every 10-year period.


What is the average population per representative based on the 2010 Census apportionment?  back to top

For the apportionment based on the 2010 Census population, the average population per representative is (COMING SOON).


When are the apportionment population counts given to the President? To the Congress? To the states?  back to top

To the President. Title 13, U.S. Code requires that the apportionment population counts for each state be delivered to the President within 9 months of the census date. In the 2010 Census and most 20th century censuses, the census date has been April 1, meaning that the Office of the President received the counts by December 31 of each census year.

According to Title 2, U.S. Code, within one week of the opening of the next session of the Congress in the new year, the President must report to the Clerk of the U.S. House of Representatives the apportionment population counts for each state and the number of representatives to which each state is entitled.

Also according to Title 2, U.S. Code, within 15 days of receiving the apportionment population counts from the President, the Clerk of the House must inform each state governor of the number of representatives to which each state is entitled.


Are undocumented residents (aliens) in the 50 states included in the apportionment population counts?  back to top

Yes, all people (citizens and noncitizens) with a usual residence in the 50 states are to be included in the census and thus in the apportionment counts.


Are children under 18 years old included in the apportionment population counts since they cannot vote?  back to top

Yes, being registered to vote or voting is not a requirement for inclusion in the apportionment counts.


When will the apportionment population counts be released to the public? Will they be posted on the Internet?  back to top

A press release showing the apportionment results will be disseminated by December 31, 2010, through a wide variety of media channels, including the Internet. A news conference announcing the apportionment results will be held shortly after.


In past censuses, where have apportionment population counts been included in the data products?  back to top

In past censuses, the apportionment population counts and the number of representatives to which each state is entitled have been included in several tables in the decennial census publications.

In 2000, for example, the apportionment results were shown in the 2000 Census of Population and Housing, Population and Housing Unit Counts, 2000 PHC-3-1. The 2000 census apportionment of the membership of the House of Representatives also is posted on the Internet at the Census Bureau’s website.


What is the difference between apportionment and redistricting?  back to top

Apportionment is the process of determining the number of representatives to which each state is entitled in the U.S. House of Representatives based on the decennial census. By law, the apportionment results must be submitted to the President by December 31 of the census year.

Redistricting is the process of revising the geographic boundaries of areas from which people elect representatives to the U.S. House of Representatives, a state legislature, a county or city council, a school board, etc. By law, redistricting data must be submitted to the states by April 1 of the year after the census.



Source: U.S. Census Bureau | Congressional Apportionment |  Last Revised: 2013-02-04T07:44:34.737-05:00