According to the Census Bureau’s American Community Survey (ACS), the U.S. population in 2010 included 39.9 million foreign-born residents. This estimate, the latest available for the foreign-born population, is 1.5 million, or 4%, higher than the survey’s 38.5 million estimate in 2009.1 A variety of additional data, however, suggest that both the absolute increase and the percentage increase in the foreign-born population were substantially smaller. An analysis by the Pew Hispanic Center, a project of the Pew Research Center, concludes that the growth in the foreign-born population from 2009 to 2010 is a markedly lower 616,000, or 1.6% (see Table 1).
The Pew Hispanic Center revision to the estimated growth in the foreign-born population was undertaken to account for changes between 2009 and 2010 in the Census Bureau’s assumptions about population composition that underlie the reported ACS estimates. This type of discontinuity in assumptions is not uncommon in government datasets, and government agencies often supply guidance to users on dealing with the issue. Pew Hispanic’s revised estimate smoothes out these discontinuities by employing the Census Bureau’s own revised and consistent set of underlying population estimates.
When the ACS data for 2009 are revised for consistency with the assumptions that underlie the 2010 ACS, the foreign-born population in 2009 is estimated to have been 39.3 million, 850,000 higher than the original ACS estimate. As a result, the growth in the foreign-born population from 2009 to 2010 is estimated to be less than originally reported.
Read the report, U.S. Foreign-Born Population: How Much Change from 2009 to 2010?, on the Pew Hispanic Center Web site.