Most unauthorized immigrants in the U.S. are not Mexican

Mexicans no longer make up the majority of unauthorized immigrants in the U.S. — a significant change from the early 2000s — as more are leaving than arriving, according to a new study by the Pew Research Center.

The big picture: The immigrant population in the U.S., which has its smallest unauthorized immigrant population in more than a decade, is markedly shifting.

• There are fewer new unauthorized immigrants now. The majority — 66% — have been in the U.S. for at least a decade. In 2000, unauthorized immigrants were more likely to have been in the U.S. for fewer than 5 years than over 10.

Between the lines: The change isn't because border enforcement has improved. Mexicans simply aren't attempting to cross the border as often as they used to. In 2000, 98% of all border patrol arrests were of Mexican nationals. Last year, Mexicans made up just 38% of border arrests, according to Customs and Border Patrol data.

• Meanwhile, there's been a surge of migrants from Central American countries, like Guatemala, El Salvador and Honduras.
• And the share of both legal and unauthorized immigrants from Asian nations has continued to grow.

Go deeper ... Chart: How immigration levels in the U.S. have changed since 1900