As the economy recovered last year, more international workers started calling the United States home.

Based on customer data from UniGroup Relocation, the international arm of the United Van Lines, 15% more people moved into the U.S. than left the country. That's up from 7% in 2012.

"It's a reflection of the strength of the economic recovery in the United States," said Richard McClure, UniGroup's CEO.

The number one place new residents are coming from: the United Kingdom. Up next: Germany, China, Australia and France.

The U.S. economy has rebounded faster than most of the Eurozone, spurring an inflow of workers from that region, explained Michael Stoll, economist and chair of the Department of Public Policy at UCLA. In addition, more U.S. companies are looking farther afield for highly skilled workers, he said.

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UniGroup's customers tend to be people who are hired for well-paid jobs. "The traffic is almost entirely corporate management," said UniGroup spokeswoman Melissa Sullivan. "People don't relocate internationally unless it's for a job."

There are some exceptions, however. The company moved quite a few elderly Chinese to America last year, McClure said. Most of them were parents of Chinese businessmen working in the U.S., he said.

Last year was the first time in four years that more people from China moved to the U.S. than the other way around. Part of that was due to the slight cooling of the Chinese economy. Another factor, is that American firms operating in China are increasingly switching to local workers so there's less need to move American employees into the country, said McClure.

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"As U.S. investments in China have matured, there's has been a movement toward homegrown talent," he said.

The total number of international moves Unigroup did fell during the Great Recession. Yet, since the recovery, the total number of moves has risen.

"You see more companies needing a presence overseas to access the increasingly global economy," said Sullivan.