'Out of about 34,000 Ph.D. recipients in science/engineering (S/E) fields awarded by US institutions in 2020, 46% (approx. 15,000) held temporary visas, a lower bound estimation of “foreign students”. Among these 15,000 recipients with temporary visas, the largest portion came from China, at 37%, three times the proportion from India, the second largest sending country'

https://www.pnas.org/doi/10.1073/pnas.2216248120