India is in the top three of legal immigration in the country accounting for a little more than 1.7 million with nearly 39 per cent being US citizens, said the study released by Center for Immigration Studies.

Out of a total immigrant population of 37.9 million, an estimated 11.3 million are illegals with 57 per cent coming from Mexico and 11 per cent from Central America.

Asia accounts for at least 9 per cent of the illegal population in the country.

The statistics showed that if about 2,22,000 people from India were registered as lawful immigrants in this country in 1980, that number has progressively increased to 3,14,000 between 1980 and 1989, to 5,39,000 between 1990 and 1999, and to 6,29,000 between 2000 and 2007, it said.

Of the total legal immigration, more than 31 per cent come from Mexico, with South Asia coming in at 5.5 per cent for a total of a little over two million immigrants.

The latest study also showed that immigrants account for one in eight US residents, the highest level in 80 years. In 1970, it was one in 21. In 1980 it was one in 16 and in 1990 it was one in 13.

Since 2000, 10.3 million immigrants have arrived – the highest seven-year period of immigration in US history. More than half of post-2000 arrivals (5.6 million) are estimated to be illegal aliens.

The largest increases in immigrants were in California, Florida, Texas, New Jersey, Illinois, Arizona, Virginia, Maryland, Washington, Georgia, North Carolina and Pennsylvania and of adult immigrants, 31 per cent have not completed high school, compared to 8 per cent of natives.

Since 2000, immigration increased the number of workers without a high school diploma by 14 per cent, and all other workers by 3 per cent.

The poverty rate for immigrants and their US-born children (under 18) is 17 per cent, nearly 50 per cent higher than the rate for natives and their children.