U.S. Population Growth Slowed Over Past Decades

U.S. population growth has slowed in the past few decades, with the South and West picking up bulking up the most in residents, according to new U.S. Census Bureau numbers released this week.

As of April 1, 2010, the U.S. resident population hit 308,745,538 individuals. That's a 9.7-percent increase from 2000 when the U.S. resident population was 281.4 million. Between 1990 and 2000, the U.S. population grew by 13.2 percent.

The U.S. resident population represents the total number of people in the 50 states and the District of Columbia.

The most populous state was California with 37.3 million residents, while the least populous, Wyoming has 563,626 residents. Texas gained the most numerically since the 2000 Census (up 4.3 million to 25.2 million), and the state that gained the most as a percentage of its 2000 Census count was Nevada (up 35.1 percent to 2.7 million).

Regionally, the South and the West picked up the bulk of the population increase, 14.3 million and 8.7 million residents, respectively. But the Northeast and the Midwest also grew coming in at 11.7 million and 2.5 million residents, respectively, as of April 1.

Additionally, Puerto Rico's resident population was 3.7 million, a 2.2-percent decrease over the number counted a decade earlier.

The count impacts how the next Congress, the 113th Congress, will be apportioned when it convenes in January 2013. The apportionment population consists of the resident population of the 50 states, plus the overseas military and federal civilian employees and their dependents living with them who could be allocated to a state. Each member of the House represents, on average, about 710,767 people. The populations of the District of Columbia and Puerto Rico are excluded from the apportionment population, since they don't have voting seats in Congress.

"The decennial count has been the basis for our representative form of government since 1790," Groves said. "At that time, each member of the House represented about 34,000 residents. Since then, the House has more than quadrupled in size, with each member now representing about 21 times as many constituents."

President Obama will transmit the so-called apportionment counts to the 112th Congress during the first week of its first regular session in January. The reapportioned Congress will be the 113th, which convenes in January 2013.

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