The number of college students claiming no religious affiliation has tripled over the last three decades, according to a professor’s analysis of a national survey of college freshmen.

More than 30 percent of incoming students last fall were among the ranks of the religiously unaffiliated, compared to just 10 percent in 1986, according to Allen Downey, professor of computer science at Olin College of Engineering in Needham, Massachusetts, who recently published his findings in a Scientific American article.

Downey analyzed data from the Cooperative Institutional Research Program (CIRP) Freshman Survey, which gathered input from 137,000 first-time students at 184 U.S. colleges and universities.

Although they are non-religious, they are not non-spiritual.

Since 1990, students have gravitated from religion at a rate of about 1 percentage point per year, according to Downey. He says most of movement is away from Catholic churches and mainline Protestant denominations.

Church attendance has also declined. The number of students attending religious services “frequently” or “occasionally” fell from 85 percent in 1990 to 69 percent in 2016.

Students who identified their sexual orientation as gay, lesbian, bisexual, queer or other were more than twice as likely to claim no religious affiliation (57 percent vs. 27 percent).

Downey noted that 98 percent of the respondents were between the ages of 17 and 19 years of age, making the results an accurate though incomplete “preview of the next generation of young adults.”

E. Scott Martin, national director of Chi Alpha Campus Ministries, says many students who claim no affiliation are nevertheless responsive to the gospel.

“We have discovered that although they are non-religious, they are not non-spiritual,” Martin says. “What we have seen in Chi Alpha is that when these students are presented with the authentic gospel of Jesus and see a role model living out His message, they are open to hearing more, and many are responding to the call to follow Jesus. We are observing the greatest number of students coming to Jesus and being baptized today than at any time in the history of Chi Alpha.”