Protestors Rally For Immigration Reform At Nation's CapitolThe number of undocumented immigrants living in the United States has stabilized since the end of the Great Recession and shows no sign of rising, according to new Pew Research Center estimates. There were 11.3 million unauthorized immigrants living in the U.S. in March 2013, according to a preliminary Pew Research Center estimate, about the same as the 11.2 million in 2012 and unchanged since 2009. The population had risen briskly for decades before plunging during the Great Recession of 2007 to 2009.

As growth of this group has stalled, there has been a recent sharp rise in the median length of time that unauthorized immigrants have lived in the U.S. In 2013, unauthorized immigrant adults had been in the U.S. for a median time of nearly 13 years—meaning that half had been in the country at least that long. A decade earlier, in 2003, the median for adults was less than eight years.

“These new estimates show that today’s unauthorized immigrants have lengthier ties to the U.S. than those in the past,” said Mark Hugo Lopez, director of Hispanic research at Pew Research Center. “A growing number and share have been in the country for more than a decade and have U.S.-born children.”

Among the nation’s 10.4 million unauthorized adults, a shrinking share have been in the country for less than five years—15% in 2012, compared with 38% in 2000. A rising share have lived in the U.S. for a decade or more—62% in 2012, compared with 35% in 2000. About a fifth (21%) had been in the U.S. for two decades or more as of 2012.

As the unauthorized population has tilted more toward long-term residents, these immigrants are more likely to have children who are U.S. citizens because they were born in the U.S. Among unauthorized immigrants, the Pew Research Center estimates that in 2012, 4 million, or 38% of adults, lived with their U.S.-born children, either minors or adults. In 2000, 2.1 million, or 30% of unauthorized adults, did. About three-quarters of unauthorized parents residing with their U.S.-born children in 2012—3 million—had lived in the U.S. for 10 years or more.

The new estimates are based mainly on data from the U.S. Census Bureau’s American Community Survey and Current Population Survey, using the widely accepted “residual methodology” employed by Pew Research Center for many years. The estimates of the total population, as well as regarding the share of unauthorized immigrants with U.S. citizen children and length of residence in the U.S., update previously published estimates.