In summary, an estimated 11.5 million unauthorized immigrants were living in the United States in January 2011 compared to a revised 2010 estimate of 11.6 million.These results suggest little to no change in the unauthorized immigrant population from 2010 to 2011. It is unlikely that the unauthorized immigrant population increased after 2007 given relatively high U.S. unemployment, improved economic conditions in Mexico, record low numbers of apprehensions of unauthorized immigrants at U.S. borders, and greater levels of border enforcement. Of all unauthorized immigrants living in the United States in 2011, 55 percent entered between 1995 and 2004. Entrants since 2005 accounted for only 14 percent of the total. Fifty-nine percent of unauthorized immigrants in 2011 were from Mexico.
The DHS report also noted that they have been working with the group that first brought us regular reports on the size of the undocumented immigrant population--Pew Hispanic Center--to make the correct adjustments for differences in estimates from the American Community Survey when based on the 2010 census compared to the previous estimates based on the 2000 census data. This assures us that we are seeing the best available figures.