Waitlist historic chances?

Son is waitlisted. Valedictorian, Soccer Team Captain, perfect ACT scores. Being from Massachusetts was not likely in his favor. Congrats to those accepted and good luck with your college choice. My question is what are his chances of gaining acceptance from the Waitlist based on past years’ data?

School’s Common Data Set actually supplies this info. Sorry for the ignorant post. More than 50 kids gained acceptance last year, but wide variability in previous years.

See EphBlog for some discussion. Sending an update with latest grades and expressing strong interest can only help.