The influx of Mexicans, which has dominated U.S. immigration patterns for four decades, began to tumble in 2006 and 2007 as the housing bust and recession created a dearth of jobs. At the same time, the number of Mexicans returning to their native country along with their U.S.-born children soared.  Stricter border enforcement, more deportations and tough state immigration laws such as the Arizona statute being challenged before the Supreme Court on Wednesday probably also contributed to the shift, says Jeffrey Passel, lead author of the report. The study analyzed data from censuses and a variety of other sources in both countries.  "There was a suspicion that people were going back" but results of the Mexican census confirmed it, he says. "They point to a fairly large number of people going back to Mexico."  From 2005 to 2010, 1.4 million Mexicans came to the USA— down by more than half from the 3 million who came from 1995 to 2000. From 2005 to 2010 , the number of Mexicans who moved from the USA to Mexico rose to 1.4 million, roughly double the number who had done so 10 years before.  Passel says the data suggest that the return flow to Mexico probably surpassed the incoming flow in the last two years.  He attributes some of the changes to lower fertility rates in Mexico (an average 2.4 children in 2009 compared with 7.3 in 1960) and improving social conditions there. According to the report, a growing share of illegal immigrants who are sent home say they won't come back to the USA — 7% in 2005 vs. 29% 2010.  Will this reversal in Mexican migration continue when the U.S. economy rebounds? "We can't tell," Passel says.  "What it does tell us is that immigration is not the weather," says Steven Camarota, director of research at the Center for Immigration Studies, which advocates controlling immigration. "It's not something that's outside the control of human agencies. It can change. … People do, in fact, go home based on the economy and based on enforcement."  Mexican flows are key to the immigration debate because 58% of the 11.2 million immigrants here illegally are Mexican. Just over half of all Mexican immigrants in the USA are here illegally.  Sen. Marco Rubio, R-Fla., last week proposed a bill that would allow young undocumented immigrants to remain in the USA but would not let them become citizens. He calls it a conservative alternative to the DREAM Act, a bill that would let young people here illegally become citizens if they attend college or join the military.  The decline in Mexican flows to the USA is not expected to soften the debate over illegal immigration, Camarota says.  "If you're someone who said, 'Let's enforce the law first and foremost,' then you think why have amnesty," he says. "The big question is what will happen if the economy begins to create jobs, what happens if some of these state laws get overturned."
In a historic reversal, Mexican immigration to the U.S. has tumbled since the recession began and more are returning home.