"Census 2000 measured a population of 281.4 million, 31.1 million (or 11.1 percent) of whom were foreign born. Individuals from Latin America represented 52 percent, Asia 26 percent, Europe 16 percent, and other areas of the world 6.0 percent of the foreign-born population. This report, part of a series that presents population and housing data collected by Census 2000, describes the distribution of the foreignborn population in the United States, regions, states, counties, and places with populations of 100,000 or more."
Census 2000 Brief C2KBR-34
Census Bureau: http://www.census.gov/