When interviewed during a 2013 Gallup poll, only 35 percent of people knew the name of their congressman or congresswoman in the U.S. House of Representatives. However, even well-known or popular representatives might fear for their jobs, not because of elections, but owing to population changes. The House sets the number of members from each state based on its population. This procedure, apportionment, has had important historical and political effects.

Count Heads

Apportionment is important because it is the reason for the U.S. Census. Although census information is used in many ways, its original purpose was to count the population for congressional apportionment. Article 1 of the Constitution set a census every 10 years. The results were to be used to determine how many seats each state has in the House of Representatives. This has been done after every census since 1790. The only exception was in 1920, when arguments between representatives from shifting urban and rural areas interfered with the process.

See the Past

Apportionment is important in historical context because the census count reflects the era. Consider minorities: before 1870, apportionment for each state was based on the number of free residents, 60 percent of the number of slaves and any Native Americans not on reservations or in unsettled areas. In 1868, with slavery gone, the 14th Amendment removed the count for slaves. However, it wasn’t until 1940 that all Native Americans were included in the census. Apportionment was also affected by geographical changes in the country. The size of the House was set at 433 in 1911, but two seats were added when Arizona and New Mexico became states. The total has remained at 435 since then, except for a short period when two seats were temporarily added for the new states of Alaska and Hawaii. Apportionment based on the 1960 census reset the number of seats to 435.

Consider the Present

Results of the 2010 census used for apportionment showed trends in society and culture. All people living in the U.S. -- citizens, noncitizens and undocumented residents – were included. The 2010 census counted overseas federal employees, both civilian and military, and their families as residents of their home states. Any U.S. citizens living abroad who weren’t federal employees weren't counted for apportionment. The total, 309,183,463, was used to determine the number of House representatives each state would have for the next 10 years. Apportionment changes were due to the population relocating. People moved to the south and west from the northeast and midwest.

Cast Your Vote

Arguably, apportionment is most important because it leads to changes in congressional districts and House seats. After the 2010 census, the population of the average congressional district was 710,767. That is almost a nine percent increase since the previous census. As a result, each member of Congress represented more people. In addition, 12 of the 435 House seats shifted. Eight states in the south and west gained seats, which meant additional votes in Congress. However, nine northeast and midwest states, along with Louisiana, lost seats, and therefore, congressional votes.