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Mr. Camarota’s report took a broad look at the immigrant population and found that immigrants are contributing to major changes in American society, including that one-fourth of public school students now speak languages other than English at home.

It also found that immigrants as a population lead complex economic lives that aren’t easily put into one category or another.

Immigrants made up more than half of all farmworkers, 41 percent of taxi drivers and 48 percent of maids and housecleaners, but they also represented about one-third of all computer programmers and 27 percent of doctors.

The statistics varied greatly by geography. In Massachusetts, native-led households averaged $89,000 in income while immigrant households averaged $66,000.

In Virginia, immigrant-led households averaged $93,000 in income, far outstripping native households’ $80,000 average. Likewise, immigrant families averaged a larger tax burden in Virginia — though they also had higher rates of use of welfare or Medicaid.

The center found that use of public benefits varied dramatically based on where immigrants originated.

Mexicans were most likely to use means-tested benefit programs, with 57 percent, while 6 percent of those from the United Kingdom did. The rate for native-born Americans is 23 percent.

Mr. Camarota said a key dividing line is educational attainment. Immigrants who have been in the U.S. 20 years and who have bachelor’s degrees or higher make slightly more than the average native-born American. But immigrants with only high school educations make less no matter how long they have been in the U.S.

“The fact is the less-educated in particular — they don’t do well over time,” he said. “It’s not reasonable to expect an immigrant who comes to America with only a high school education to close the gap with the native-born.”

Scholars debate whether the current wave of immigrants will assimilate differently from those in the 1800s and at the start of the 20th century.

George Borjas, a Harvard University professor, has argued that second-generation Americans — the children of today’s immigrants — will fall behind in wages by about 10 percent by 2030.

But in “Assimilation Tomorrow,” a report released in November, Dowell Myers and John Pitkin said immigrants of the 1990s eventually will attain high rates of homeownership and 71 percent will become U.S. citizens by 2030.

Those authors said immigrants were set back by the recent recession but were still on track to follow the same assimilation path as previous waves of immigrants.

They also said a program to legalize the estimated 11 million illegal immigrants in the U.S. would be critical to helping assimilation.