International student enrollment in the U.S. fell by 15 percent during the 2020-2021 academic year amid the COVID-19 pandemic, the largest single drop since the government and nonprofit groups began recording data in the late 1940s.

A total of 914,095 international students were enrolled in U.S. colleges and universities last school year, according to data collected by the Institute of International Education and jointly released Monday with the State Department. That reflects a decline from nearly 1.1 million the previous year that reflects the ravages of the pandemic.

Broad travel restrictions and delayed visa processing limited international student enrollment, said Mirka Martel, head of research, evaluation and learning at IIE. Many U.S. consulates in foreign countries suspended operations as the pandemic spread, or conducted only limited services.

“The 2021 academic year was a historic moment for international exchange and student mobility due to the global shock of the COVID-19 pandemic,” Martel said during a briefing Monday morning. “Many international students were not able to travel to the United States due to travel restrictions.”

New student enrollment plummeted by 46 percent, the primary driver of the overall 15 percent decline. Current student enrollment was far more resilient, declining only 3 percent.

“This indicates that international students who were already enrolled at U.S. universities were committed to continuing education this year,” Martel said.

IIE surveyed roughly 3,000 educational institutions to compile the annual report. This year, they expanded the definition of “international student” to reflect online programs in which international students studied virtually at a U.S. university while in their home country.

Preliminary data for the 2021-2022 academic year suggests a likely rebound, with enrollment up 4 percent in the fall 2021. But the sharp decline last year raises concerns in part because of the role foreign students play in the U.S. economy.

International students, who often pay full tuition at U.S. colleges, contributed $28.4 billion to the U.S. economy during the 2020-2021 academic year, down nearly 27 percent from the previous year, according to additional data released by NAFSA: Association of International Educators.

“We know that U.S. colleges and universities are working tirelessly to support international students in a safe and effective manner during this challenging time,” Esther D. Brimmer, NAFSA’s executive director, said in a statement. “Their efforts would be greatly assisted by a coordinated governmental approach that both attracts and retains international student talent.”

Brimmer said the Biden administration should adopt a “comprehensive national strategy” to restore international student enrollment in the United States.

Matthew Lussenhop, acting assistant secretary at the State Department’s Bureau of Educational and Cultural Affairs, told reporters in Monday’s briefing that the government continues to “focus on rebuilding academic exchanges and student mobility post-pandemic.”

“We look forward to collaborating with our friends and colleagues across the higher education sector to build back better from the pandemic,” he said.