US: A rapid rise in the immigrant workforce in the US did not have a negative impact on job prospects for native-born workers, according to a study released by a think tank.
The report, by the Washington-based Pew Hispanic Center, looked at the relationship between growth in the foreign-born population and the ability of US-born workers to get jobs from 1990 through to 2004.
According to the US Census Bureau, 34.2 million people living in the United States in 2004 were foreign-born. More than half of these arrived in the country since 1990.
"No consistent pattern emerges to show that native-born workers suffered or benefited from increased numbers of foreign-born workers," the study, by the centre's Rakesh Kochlar, said.
The report comes as Congress is deadlocked over a proposal by President Bush to overhaul immigration laws and offer a path to citizenship to many of the US's 12 million illegal immigrants.
The Pew report drew on census data and examined two timeframes: the economic boom years from 1990 to 2000 and the recession and recovery years from 2000 to 2004.
It found that in both periods, nearly a quarter of native-born workers lived in states where rapid growth in the foreign-born population had a favourable impact on job prospects for the native-born.
Fifteen per cent of US-born workers lived in states where rapid growth in the immigrant population was associated with negative outcomes for the native-born, according to the report.
The remaining 60 per cent of US-born workers lived in states where the growth in the immigrant population was below average, but those native workers did not consistently experience positive employment outcomes.
The report did not include analysis of the impact of foreign-born workers on salary levels in the US, which is a concern to some activists seeking to crack down on illegal immigration.