Immigrants are responsible for close to a quarter of New York State’s economy and are not only 70% of New York City’s cooks and construction workers and 90% of its taxi drivers, but half of the city’s doctors and accountants and a quarter of the CEOs, according to a report to be released today.

The report, by the Fiscal Policy Institute, a left-leaning think tank backed by public employee unions, found that foreign-born residents were responsible for $229 billion of New York’s economy last year — more than the individual gross domestic product of 30 states.

The number of immigrant-owned businesses also climbed rapidly in recent years, and immigrants have branched into top occupations, according to the report, which based many of its findings on Census data.

RELATED: The Fiscal Policy Institute Report (pdf)

The report’s main author, David Dyssegaard Kallick, a Fiscal Policy Institute senior fellow, said he was expecting to find that immigrants have a positive economic impact — but “was surprised at just how robust the immigrant contribution is.”

The report, which was also sponsored by the New York Immigration Coalition, could give momentum to immigrant advocates, who have been trying to pick up the pieces after a bill to overhaul the national immigration system failed last summer and Governor Spitzer recently retracted a plan to give driver’s licenses to illegal immigrants.

“For us to maximize immigrant contributions to the economy, we must stop treating immigrants like criminals and terrorists,” the executive director of the New York Immigration Coalition, Chung-Wha Hong, said in response to the report. “Instead, we need to change our immigration laws so that undocumented immigrants can come out of the shadows of the underground economy and future immigrant workers can immigrate legally to fill jobs that our economy requires.”

The findings could also vault New York State’s immigrants back into the fray of the presidential campaign. Immigrants make up more than a fifth of the state’s population, compared to their 12% share of the national population, and candidates on both sides of the immigration debate have often found themselves focused on New York when grappling with the delicate political issue.

A Republican candidate, Fred Thompson, has attacked Republican hopeful Rudolph Giuliani, the former mayor, for allowing the city to be a “sanctuary” for illegal immigrants, while Senator Clinton, running for the Democratic presidential nomination has had to fend off criticism for hesitating about her reaction to Mr. Spitzer’s driver’s license plan. About 3 million of New York City’s 8.2 million residents are immigrants, the report says, and 57% of the children in New York City live in a family with at least one foreign-born adult.

Mr. Dyssegaard Kallick predicted the report would “wipe away” some negative impressions of immigrants, however.

“People often assume that immigrants are concentrated at the low end of the economic spectrum,” he said. “In New York City they were so much at the top, middle, and bottom of everything.”

The report noted that some researchers have found that immigrants in low-wage jobs may impact negatively on native workers with less than a high school education. While Mr. Dyssegaard Kallick didn’t dispute this, he said his most striking finding was the extent to which immigrants — who make up more than a third of the city’s residents — are concentrated in the middle-income levels, as defined by the report. In the city, immigrants are more likely than citizens to earn middle-income salaries, the report said, with 55% of immigrant families earning between $20,000 and $80,000 a year, compared to 44% of native born families.

“Immigrants are helping stabilize the middle class at a time when there’s a lot of pressure — there’s the big middle class squeeze,” Mr. Dyssegaard Kallick said.

Part of the report by Pew Hispanic Center researcher Jeffrey Passel focused on the city’s illegal immigrants — about half a million people. Many work in low-wage professions, including dishwashing, sewing, and maintenance. He estimated that 70% of all illegal immigrants in the city are working, compared to labor force participation rates of 64% for immigrants in general, and 60% for native-born New Yorkers.

The report found that immigrants work about an hour longer a week than native-born workers, but earn less money. Many are also now expanding into the surrounding suburbs, where they make up 18% of the population, and are becoming commuters.

The report argues that immigrants, who are expanding in number even as the native population of the city dips, have given “new life to a declining city.”

Still, some disparities exist between residents and immigrants. Native workers in the city make between nine and 19% more than immigrants with the same level of education, the report said. In particular, foreign-born Hispanics with a college degree earn less than their native born counterparts.

The 121-page report was funded by the Carnegie Corporation of New York, the New York Community Trust, and the Horace Hagedorn Foundation, a Long-Island based foundation created by the marketing genius behind Miracle-Gro plant food.