Next Tuesday, the nation will see the very first results from the 2010 Census when the U.S. Census Bureau releases the total population counts for the nation and each state. These counts will show us how our population has grown and shifted over the last decade. As mandated by the U.S. 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 – known as apportionment. The number of seats in the House has grown with the size of the country. Congress sets the number by law, which was most recently increased to 435 in 1913. Back in 1787, the Constitution set the number of representatives at 65 until the first Census of 1790, when it was increased to 105 members. But how does apportionment actually work? 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 in its new apportionment video.