One in Seven Mexican Workers Now Work in US
Ironically, one cause of the increase may be better border enforcement, effectively trapping Mexicans in the US who might otherwise cross the border back to Mexico.
In 2005, 9.4% of native Mexicans were living in the US, and 14% of working Mexicans had jobs in the US (as opposed to 2.5% of working Canadians). This year, Mexicans accounted for nearly 5% of the total US civilian workforce.
Source: Reuters (via Yahoo)