FOR RELEASE MARCH 2, 2011

If there are now fewer unauthorized immigrants in the U.S. where did they go?

Senior research staff answer questions from readers relating to all the areas covered by our seven projects, ranging from polling techniques and findings, to media, technology, religious, demographic and global attitudes trends.

BY Michael Suh

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Pew Research Center, March 2011, "If there are now fewer unauthorized immigrants in the U.S. where did they go?"

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If there are now fewer unauthorized immigrants in the U.S. where did they go?

Senior research staff answer questions from readers relating to all the areas covered by our seven projects, ranging from polling techniques and findings, to media, technology, religious, demographic and global attitudes trends.

Q. Your recent report indicated that in 2009 and 2010 there were many fewer undocumented immigrants in the United States than in earlier years. Is there any information on where these folks went?

Various factors could account for the decline in the number of unauthorized immigrants in the U.S. in recent years. First, the balance of immigrant flows in and out of the U.S. could have changed, so that the number of newly arriving unauthorized immigrants could be smaller than it used to be, or the number who are leaving could be larger. Second, some unauthorized immigrants could have converted their status by obtaining U.S. citizenship or other legal authorization.

We do have one important clue in trying to determine why the overall numbers declined. The decline in the population of unauthorized immigrants, from 12 million in 2007 to 11.2 million in 2010, is due mainly to a decline in the population of unauthorized immigrants from Mexico. Their numbers declined from 7 million in 2007 to 6.5 million in 2010, although Mexicans still make up the bulk of unauthorized immigrants (58%). Also, analysis of Mexican government data shows that the number of immigrants returning to Mexico each year has declined slightly — about 480,000 Mexicans returned home in 2006 compared with 370,000 in 2009. However, these same data sources suggest that the number of Mexicans migrating to the U.S. (or other countries) fell by almost half from just over 1 million in 2006 to about 515,000 in 2009.

Jeffrey S. Passel, Senior Demographer, Pew Hispanic Center