In a report based on an analysis of U.S. Census Bureau data, Pew said although the number of immigrants reached an all-time high, immigrants did not account for a record percentage of the total population. The current share, 13 percent in 2011, compares to a peak share of nearly 15 percent from 1890 to 1920, when the United States took in large numbers of immigrants from Europe.
Of the current immigrant population, 50 percent are from Latin America and 27 percent are from Asia.
The total number of immigrants has increased by more than 9 million since 2000. The number of unauthorized immigrants has fallen from its peak of 12 million in 2007 to 11.1 million in 2011.
The report said unauthorized immigration fell largely because of a reduction in immigration from Mexico, which had accounted for 58 percent of unauthorized immigrants in 2010.
Nearly two-thirds of all unauthorized immigrants in 2010 had lived in the United States for at least 10 years, and 46 percent were parents of minor children.
The report is available online at the Pew Hispanic Center website, www.pewhispanic.org.