Pew Hispanic reports that net immigration from Mexico might have fallen to zero or even reversed (link, [1]).

This is clear evidence that attrition (aka "self deport") works: many Mexican illegal aliens have made the rational decision to return to their home countries.

This is also the establishment implicitly admitting that attrition works. To recap, back in January, Mitt Romney mentioned attrition (referring to it as "self deport") during a debate. Some in the Democratic Party base were quickly trained to mock "self deport" and to (incorrectly) treat it as a new plan. Newt Gingrich mocked it, Wolf Blitzer lied about it.

Then, in February, a Center for American Progress study unwittingly admitted it works. Just this month, Michael Barone admitted it works.

Now comes Pew Hispanic with their study, which has been picked up by several establishment media sources. The cat's fairly much out of the bag, but illegal immigration supporters are spinning it as evidence not so much that attrition works but that we don't need as much immigration enforcement as we do. Since most of the movement to Mexico is no doubt caused by the economic downturn, when the U.S. economy improves the inflow might return to previous levels.

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[1] The "key findings" from the link:

* In the five-year period from 2005 to 2010, about 1.4 million Mexicans immigrated to the United States and about 1.4 million Mexican immigrants and their U.S.-born children moved from the United States to Mexico.

* In the five-year period a decade earlier (1995 to 2000), about 3 million Mexicans had immigrated to the U.S. and fewer than 700,000 Mexicans and their U.S. born-children had moved from the U.S. to Mexico.

* This sharp downward trend in net migration has led to the first significant decrease in at least two decades in the number of unauthorized Mexican immigrants living in the U.S.—to 6.1 million in 2011, down from a peak of nearly 7 million in 2007. Over the same period the number of authorized Mexican immigrants rose modestly, from 5.6 million in 2007 to 5.8 million in 2011.

* Mexicans now comprise about 58% of the unauthorized immigrants living in the United States. They also account for 30% of all U.S. immigrants. The next largest country of origin for U.S. immigrants, China, accounts for just 5% of the nation’s stock of nearly 40 million immigrants.

* 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. This decline has occurred at a time when funding in the U.S. for border enforcement—including more agents and more fencing—has risen sharply.

* As apprehensions at the border have declined, deportations of unauthorized Mexican immigrants—some of them picked up at work or after being arrested for other criminal violations—have risen to record levels. In 2010, nearly 400,000 unauthorized immigrants—73% of them Mexicans—were deported by U.S. authorities.

* Although most unauthorized Mexican immigrants sent home by U.S. authorities say they plan to try to return, a growing share say they will not try to come back to the U.S. 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.

* Looking back over the entire span of U.S. history, no country has ever sent as many immigrants to this country as Mexico has in the past four decades. However, when measured not in absolute numbers but as a share of the immigrant population at the time, immigration waves from Germany and Ireland in the late 19th century equaled or exceeded the modern wave from Mexico.