Immigrants living illegally in the U.S. held fewer blue-collar jobs and more white-collar ones in 2012 than they did before the Great Recession, yet a majority still work in low-skilled service, construction and production occupations, a new report shows.

Based on census data, the Pew Research Center report says the number of immigrants without legal status working or looking for work in the U.S. did not change from 2007 to 2012, when the total was 8.1 million. But the number holding management or professional-related jobs grew by 180,000, while the number in construction or production jobs fell by 475,000. Those changes mirror rises and declines in the overall U.S. economy, the report says.

An estimated 275,000 immigrants without legal status were in Georgia’s labor force in 2012, the report says. Of those, 31 percent were working in the service industry, 20 percent held construction jobs and 13 percent worked in production. Farming is the occupation with the highest share of such workers in Georgia at 23 percent, followed by construction, 21 percent; and production, 11 percent.

“Because unauthorized immigrants tend to have less education than people born in the U.S. or legal immigrants, they are more likely to hold low-skilled jobs and less likely to be in white-collar occupations; further, their status limits job opportunities,” Jeffrey Passel, a senior demographer for Pew, said in written testimony he prepared to deliver to Congress Thursday. “Consequently, unauthorized immigrants tend to be overrepresented in certain sectors of the economy.”