U.S. students have been urged in the past few years to pursue careers in STEM-related industries due to a shortage of American tech employees, but a new report by the Institute for Regional Studies found Silicon Valley tendency to hire foreign-born workers.

The tech hub has a significantly higher population share that is foreign-born than are U.S. citizens or California residents. Thirty-seven percent of Silicon Valley's population are non-citizens who entered the U.S. to fill a specific job in the tech industry. Compare that to California's 27 percent of the population that is from another country and a 13 percent national average.

Nearly three-quarters — 74 percent — of Silicon Valley-employed computer and mathematical workers ages 25 to 44 are foreign-born, according to the 2016 Silicon Valley Index, which is released every February.

"I wonder if high school guidance counselors and the science and technology professors tell the kids about this when encouraging them to go into the STEM field? I would be absolutely depressed to find that out. Where is the outrage?" a GOP congressional aide told the Washington Examiner on Friday.

While Silicon Valley groups have claimed a shortage of STEM workers prompted their external hiring, others have said it's untrue.

"In a desert of evidence, the growth of STEM shortage claims is driven by heavy industry funding for lobbyists and think tanks. Their goal is government intervention in the market under the guise of solving national economic problems," Hal Salzman, a sociologist and professor at Rutgers University, argued in 2014.

"The highly profitable IT industry, for example, is devoting millions to convince Congress and the White House to provide its employers with more low-cost, foreign guestworkers instead of trying to attract and retain employees from an ample domestic labor pool of native and immigrant citizens and permanent residents," Salzman added.

The new report leaves questions to be answered, including if Silicon Valley claimed a worker shortage in order to source cheaper foreign labor instead of IV League STEM graduates.