Mexican migration into the United States has come to a standstill and may soon reverse, according to a report by the Pew Hispanic Center. This marks a dramatic change in the wave of Mexican migration that brought 12 million people to America over four decades.

About 1.4 million Mexicans immigrated to the United States between 2005 and 2010, which is roughly the same number of Mexicans who left over the same period.

The number of illegal immigrants from Mexico dropped from 7 million in 2007, a peak, to 6.1 million in 2011. The report attributes the drop to the drastic decline in birthrates in Mexico, the increasingly dangerous passage across the border, and the flagging American economy. A higher percentage of deported migrants now say in surveys that they will not attempt to come back into the United States (compared to 10 years ago).

The United States' estimated 12 million Mexican immigrants represent the largest chunk of immigrants in any country in the world. Mexico has sent more immigrants to the States over the past four decades than any other nation.

According to the Mexican census, 500,000 U.S. citizen children were living in Mexico in 2010, compared to 240,000 10 years earlier. Government data doesn't say how many of those children left the United States because their parents were deported.

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