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Border Patrol agents detain undocumented immigrants apprehended near the Mexican border.
The number of Mexican immigrants living illegally in the U.S. has dropped significantly for the first time in decades a new study suggests.
The figures represent a dramatic shift as many illegal workers, already in the U.S. and seeing few job opportunities, are returning to Mexico.
The analysis of census data from the U.S. and Mexican governments finds that roughly 6.1 million unauthorized Mexican immigrants were living in the U.S. last year. That's down from a peak of nearly 7 million in 2007.
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The Pew Hispanic Center report attributed much of the drop to a weak U.S. economy, which has shrunk construction jobs attractive to Mexican workers. But increased deportations, heightened U.S. patrols and violence along the border as well as Mexico's declining birth rate, also have played a role.
The report is based on the Center’s analysis of data from five different Mexican government sources and four U.S. government sources.
In a breakdown of key points, the Pew Hispanic Center pointed out that apprehensions of Mexicans trying to cross the border illegally have plummeted by more than 70% in recent years, from more than 1 million in 2005 to 286,000 in 2011—a likely indication that fewer unauthorized immigrants are trying to cross.
Instead, deportations of unauthorized Mexican immigrants have risen to record levels, researchers report. Nearly 400,000 undocumented immigrants were deported by U.S. officials in 2010.
Of that number, 73 percent were Mexicans.
Most undocumented immigrants sent home to Mexico say they plan to try and return to the U.S. However, a growing number said they would not try to come back to the U.S. according to the research.
According to a survey by Mexican authorities of repatriated immigrants, 20% of labor migrants in 2010 said they would not return, compared with just 7% in 2005.
Diana Guevara covers stories involving San Diego's Latino community. Send her your thoughts via Twitter @nbcsandiego or add your comment to our Facebook page.
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