Census: Immigration helps big metros grow

Without immigrants pouring into the nation's big metro areas, places such as New York, Los Angeles and Boston would be shrinking as native-born Americans move farther out. "Immigrants are filling the void as domestic migrants are seeking opportunities in other places," said Mark Mather, a demographer at the Population Reference Bureau, a private research organization. Immigrants long have flocked to major metropolitan areas and helped them grow. But increasingly, native-born Americans are moving from those areas and leaving immigrants to provide the only source of growth Without immigration, the Los Angeles metro area would have lost more than 200,000, the San Francisco area would have lost 188,000 and the Boston area would have lost 101,000.