The Pew Research Center said population statistics compiled by the U.S. Census Bureau show no statistical variance in the number of illegal immigrants estimated to be living in the country in 2012, the most recent year for which information is available.
The estimated number of illegal immigrants peaked in 2007, the year before the recession, at 12.2 million. By 2009, the number had fallen to 11.3 million. The numbers have mostly held steady -- and within the wide statistical margin of error for such a study. In 2010, there were an estimated 11.3 million illegals. That rose to 11.5 million in 2011 and 11.7 million in 2012, Pew said.
And given the Census statistics have grown more precise in recent years, Pew said it's possible the actual number of illegals may have increased.
Pew said Mexicans still account for the largest percentage of illegal immigrants at 52 percent of the total alien population.
The study's margin of error varies from year to year depending on the sample size.