The U.S. population has grown 9.7 percent in the past decade — the smallest growth rate since 1930-40, according to the first results of the 2010 decennial census released today.
The U.S. Constitution mandates that the census be conducted every 10 years in order to redistribute seats in the U.S. House of Representatives proportionally by population. Census figures also allow businesses to gauge new markets and determine the distribution of funds for several federal programs including health care, education, and unemployment insurance.
The official count for the U.S. resident population as of April 1, 2010 was 308,745,538, up from 281,421,906 in 2000.
Put in a historical context, the nation had a population of 3.9 million at the time of the first census in 1790. By 1910, that population had risen to 92.2 million and grew at a double-digit rate nearly every decade after that.