The U.S. population clock is at 304, 633,590, but the scary number is the growth rate, 4,315,000 births in 2007, more than double the number a century ago, and topping the number born in 1957 at the height of the post-war baby boom. ...birth rates for females ages 15 to 19 fell below rates for older women ages 35 to 39.
The biggest factor by far is immigration. The birth rate among Hispanic immigrants far outpaces the modest 2.1 average births per women. A decade ago, Hispanics made up 40 percent of the nation's increase in population. From 2000 to 2004, that number jumped to 49 percent. The ethnic group has more than three times the growth of the national population ...
Asian immigration now mirrors what Hispanic growth once was, with new immigrants coming from countries like India, China and the Philippines, Mr. Passel said. The Asian growth rate is a close second to the Hispanic rate and is also more than three times the growth of the national population.
Though immigration among Hispanics peaked about five years ago, it continues at a steady pace, Mr. Passel added. But Hispanic babies born in the United States now outnumber new immigrants. One in five children under 18 is Hispanic, according to census figures.
An estimated 41.3 million residents living in the United States legally or otherwise are Hispanic. Experts say younger voters may energize the Hispanic voting bloc, "As this population gets older, it will become a much more powerful political force," said Audrey Singer, an immigration fellow at the Brookings Institution in Washington.
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