A federal training program that allows foreign students to stay and work in this country after graduating from a United States college or university saw a 400 percent increase in foreign students graduating and working in STEM fields from 2008 to 2016.

Between 2004 and 2016, nearly 1.5 million foreign graduates of U.S. colleges and universities obtained authorization to remain and work in the U.S. through the federal government’s Optional Practical Training program (OPT). More than half of the foreign graduates approved for employment specialized in science, technology, engineering, and mathematics (STEM) fields according to a Pew Research Center analysis of U.S. Immigration and Customs Enforcement (ICE) data received through a Freedom of Information Act request.

The Optional Practical Training program was developed to allow F-1 visa holders to gain practical work experience after graduating from a U.S. college or university. In 2007 and 2013, Congress did not pass expansive reforms to the H-1B visa program as part of comprehensive immigration reform bills. At the time, there were proposals to increase the number of H-1B visas as well as legislation to add 55,000 green cards exclusively for foreign student graduates with a STEM degree.

Many foreign STEM graduates enrolled with OPT after executive actions in 2008 and 2016 initially doubled (29 months), then later tripled (36 months), the maximum length of employment for foreign students with STEM degrees.

OPT is one mechanism by which the U.S. can compete with other countries for top talent. It is less well-known than the H-1B visa program – which enables U.S. companies to hire highly skilled foreign workers and is the nation’s largest temporary employment visa program – yet OPT approvals actually outnumbered initial H-1B visa approvals in recent years.

According to the Pew Research Center analysis, between 2004 and 2016, the number of foreign student graduates who were approved for the OPT program rivaled the number of high-skilled workers initially approved for the H-1B visa program. By the end of the 2004-2016 period, there were a total of 1,474,000 OPT approvals and 1,473,000 initial H-1B visa approvals.

Both the OPT program and the H-1B visa give foreign workers temporary employment authorization in the U.S., but they are different in a number of ways. For instance, only foreign students on an F-1 visa with a higher education degree from a U.S. college or university are eligible for the OPT program, whereas any foreign worker with a degree that is equivalent to a U.S. bachelor’s degree or higher is permitted to apply for the H-1B visa. Also, unlike the H-1B visa program, which imposes an annual cap of 65,000 visas to private companies sponsoring foreign workers, there is no cap on the number of approvals available under the OPT program; all F-1 visa holders are eligible to apply.

Foreign students obtaining authorization to remain and work in the U.S. after graduation come from all corners of the globe, but the majority of them hold citizenship in Asia. Students from India, China and South Korea made up 57 percent of all OPT participants between 2004 and 2016.