The flow of immigrants to the United States has resumed, after falling to the lowest level in decades during the recession, a new study finds.

The number of immigrants in the United States was estimated to have risen by about a half-million in the year that ended in 2009, a jump from the previous year, when immigration stopped almost completely during the recession, according the study, which was conducted by the Brookings Institution and is being released on Thursday.

The rise pointed to an increase in demand for immigrant labour in the economy, said Audrey Singer, a demographer and co-author of the report.

However, the number is still far below the increases of more than a million a year that took place earlier in the decade. The flow reached a peak in 2006, with a 1.8 million increase in the foreign-born population.

“It's an uptick in opportunity,” Ms Singer said. “Immigrants are very mobile in responding to economic changes.”

In 1980, the foreign-born population in the United States was about 4.5 million. By 2000, it had reached 11.3 million, bringing the foreign-born population to about 13 per cent of the total. In the early 20th century, after the last big wave of immigration to the United States, immigrants had reached 15 per cent of the population.

In 2008, immigration came to a standstill, the first big slowdown in decades of surging numbers, according to the report, which was based on estimates by the Census Bureau. Last year, the foreign-born population stood at 7.4 million.

“After three decades of nonstop growth, immigration seems to have paused,” the report says.

The biggest losses were in cities that had boomed in recent years, particularly in the housing industry, including Phoenix, Riverside and San Bernardino in California and Tampa, Florida.

Cities where the recession had less of an effect, including Austin, Texas; Houston; Raleigh, N.C.; and Seattle, continued to gain immigrants.

The biggest increases came in smaller metropolitan areas that had little or no immigrant populations before. Among them were Jackson, Mississippi, whose foreign-born population grew by half in the two years ending in 2009; Birmingham, Alabama, where immigrants increased by a quarter; and Worcester, Massachusetts, and Omaha, which both experienced growth of about 20 per cent, according to the report.

There was a slight rise in the portion of immigrants without a high school education, though the report noted that it was unclear whether this was because of low-skilled immigrants already in the United States, or because of less educated ones arriving. Immigrants with a bachelor's degree did not change, the report said. — New York Times News Service

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