http://www.nytimes.com/2009/05/15/us/15immig.html?hp

By JULIA PRESTON
Published: May 14, 2009

MEXICALI, Mexico — Census data from the Mexican government indicate an extraordinary decline in the number of Mexican immigrants going to the United States.

The recently released data show that about 226,000 fewer people emigrated from Mexico to other countries during the year that ended in August 2008 than during the previous year, a decline of 25 percent. All but a very small fraction of emigration, both legal and illegal, from Mexico is to the United States.

Because of surging immigration, the Mexican-born population in the United States has grown steeply year after year since the early 1990s, dipping briefly only after the attacks of Sept. 11, 2001, census data in both countries show.

Mexican and American researchers say that the current decline, which has also been manifested in a decrease in arrests along the border, is largely a result of Mexicans’ deciding to delay illegal crossings because of the lack of jobs in the ailing American economy.

The trend emerged clearly with the onset of the recession and, demographers say, provides new evidence that illegal immigrants from Mexico, by far the biggest source of unauthorized migration to the United States, are drawn by jobs and respond to a sinking labor market by staying away.

“If jobs are available, people come,â€