Manufacturing jobs used to be a path to the middle class. But now many skilled, working Americans need some form of public assistance because their wages don't pay for basic living expenses. Over 2 million supervised manufacturing workers, or about a third of the total, need food stamps, Medicaid, tax credits for the poor or other forms of publicly subsided assistance while they work on goods that can carry the tag Made in the U.S.A.," according to research of official government wage and welfare data released Tuesday by the University of California, Berkeley. The cost of these benefits to the U.S. taxpayer? From 2009 to 2013, federal and state governments subsidized the low manufacturing wages paid by the private sector to the tune of $10.2 million per year. "In decades past, production workers employed in manufacturing earned wages significantly higher than the U.S. average, but by 2013 the typical manufacturing production worker made 7.7 percent below the median wage for all occupations," said the paper. The research aimed to extend an already well-established national debate on wages paid in the service industry, which are often juxtaposed to the factory work that lifted millions of Americans out of poverty for much of the 20th century. The research comes as U.S. workers overall are experiencing one of the lowest paces of wage growth on record.