SAN DIEGO—Move over, Mexico. When it comes to sending immigrants to the U.S., China and India have taken the lead.

China was the country of origin for 147,000 recent U.S. immigrants in 2013, while Mexico sent just 125,000, according to a Census Bureau study by researcher Eric Jensen and others. India, with 129,000 immigrants, also topped Mexico, though the two countries’ results weren’t statistically different from each other.

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