More Mexican immigrants are now leaving the United States than entering, according to a Pew Hispanic Center study.
The number of illegal immigrants caught trying to cross the border into the U.S. dropped from more than one million in 2005 to 286,000 last year.
That's a decrease of more than 70%.
Mexicans make up almost a third of all immigrants who are currently in the country.
More than half are here illegally.