If the approximately 1.2 million foreign-born residents of Miami-Dade County, Fla., composed a city of their own, it would be among the 10 largest U.S. cities. That's just one of the statistical gems in the Census Bureau's recently released American Community Survey, which makes us wonder if home builders are ready for recent immigration's impact on local housing markets.

The ACS, which surveyed more than 742,000 households in 2002, will expand to 3 million households next year and replace the census long form in 2010. The 2002 study shows that America's foreign-born population grew to more than 33 million last year. At right are the five cities and five states with the highest percentage of foreign-born population.