For the latest reported period (2021/22), Princeton waitlisted 1,265 (essentially the same as the incoming class size), or over 3/4s of the number (1,647) they admitted that year.
Roughly 12% of the waiting list was accepted.
For 2022 admissions (class of 2026): admitted 5.7% (2,167 of 38,019) for a class of 1,500, so almost 70% yield. I don’t see the size of the corresponding waitlist: