FORTUNE – As Congress debates the future of the nation’s immigration laws, lots of attention has been paid to highly skilled workers graduating from top U.S. Universities. The biggest names in the tech industry have lobbied to make it easier for them live and work in America. They say many versed in science, technology, engineering, and math graduate from the nation’s top universities only to live years in legal limbo waiting for green cards. By allowing more to stay, the U.S. Economy would be more competitive than others.
That may be true, but a new report argues engineers, programmers, and the like aren’t the only jobs that fall in STEM fields — otherwise known as science, technology, engineering, and math. Think registered nurses, car mechanics, plumbers and electricians. Their jobs may not require a college degree, but they are nonetheless highly technical. And they help the economy grow.
By including such jobs, the nation has more STEM jobs than previously thought, according to a report released by Brookings Institution. In 2011, 20%, or 26 million, of all U.S. Jobs require a “high level” of knowledge in any one STEM field. That compares with the 4% to 5% estimated by the National Science Foundation.
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They may not be the inventors or innovators, but they are decently paid, says Jonathan Rothwell, associate fellow at Brookings who authored the report. On average, STEM jobs that don’t require a bachelor’s degree pay $53,000 a year — more than an average of $33,000 a year paid for jobs that neither require a bachelor’s degree nor fall in STEM fields. And unlike STEM jobs held by college grads, these positions aren’t concentrated in familiar tech hubs, such as Silicon Valley. They’re dotted around the country and are also concentrated in cities including Baton Rouge, La., Birmingham, Ala., and Wichita, Kan.
This isn’t to say that immigration reform should overlook the most highly skilled math and science gurus — a significant portion of whom come from outside the U.S. In 2010, nearly half, 45%, of master’s and doctoral students in engineering were from abroad, according to the latest data from the National Science Foundation.
For more than a decade, students from abroad have increasingly pursued engineering, as well as science and health programs in the U.S. In 2010, approximately 632,700 graduate students were enrolled in science, engineering, and health programs, up 30% from about 493,300 students in 2000, according to the foundation. In particular, studies in biomedical engineering saw the most rapid growth, with enrollment during the same period rising by 165% to 8,500 graduate students.
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But while people like Facebook (FB) founder Mark Zuckerberg are lobbying to get more college-educated foreigners to stay in the country, let’s not forget about jobs that involve math and science but don’t require a degree. Rothwell urges the government to adopt a broader definition of STEM jobs, so that such jobs get more funding for education and training. Of the $4.3 billion spent by the federal government on STEM education, only 20% goes toward education or training below the bachelor’s degree level.
What’s more, the proposed immigration bill would put more federal funds toward universities at the expense of vocational schools and the like.
