US Population Growth Slows Down April 29, 2021 FILE - In this Monday, Jan. 11, 2021, file photo, people overlook the skyline of Los Angeles. California is losing a U.S. House seat for the first time, dropping its delegation from 53 to 52 members. Share share The URL has been copied to your clipboard 0:00 0:05:12 0:00 Pop-out player The United States population has slowed to its lowest rate since the 1930s, the Census Bureau said Monday. Every ten years, the Census Bureau counts the country’s people. The total U.S. population is now 331,449,281. It is 7.4 percent more than ten years ago, but the second slowest increase ever. Experts say the slow rate is due to an older population, less immigration and the effects of the Great Recession. The 2008 economic crisis led many young adults to wait to get married and have families, which slowed the birthrate.