The mid-2010s saw an increase in college closings in the US, particularly among private, for-profit schools. The trend has affected tens of thousands of college students across the country.

Since 2016, 91 private colleges in the U.S. have closed, merged with another school or announced plans to close, according to a CNBC analysis of data from Higher Ed Dive. Almost half of these schools closed after the outbreak of the Covid pandemic in 2020. For many struggling schools, the pandemic was the last straw – but two main themes kept coming up during the closures: finance and enrolment.

“There are two significant issues affecting higher education right now, specifically through the admissions and registrar’s offices,” said Robert Franek, editor-in-chief of The Princeton Review. “Number one, that’s the entrance cliff, and that’s the impending drop [in the number of prospective students]. In 2025, we will graduate from our lowest high school classes by population. And most enrolling professionals have been wringing their hands over that 2025 date, but many schools have already seen that decline.”

About 95% of America’s colleges are tuition-based, meaning they rely on money from students to operate, according to Franek. Declining enrollments mean less money, fewer student offers, and ultimately a closed institution.

“I think it’s a reflection of an unsustainable operating platform, which means a heavy reliance on tuition fees that can’t always keep up with inflation. [or] with enrollment erosion,” said Fitch Ratings senior director Emily Wadhwani. Colleges “can’t hold the price of tourist tuition in the hope that the net residual, once you factor in scholarship and discounts and the like, will be enough to offset your growth in cost base.”

Watch the video above to learn about the challenges facing higher education and hear from students affected by college closures.