It was 55% in 2016, do you think it’ll be higher or lower now?
Look at the Purdue Data Digest under “Applications, Admits, and Matriculations,” and insert the parameters that are appropriate to you. There should be a table at the bottom which gives the admission rates (and yield) for students matriculating in the Fall semesters of the past 10 years.
The acceptance rates have been broadly trending down for foreign undergraduate applicants to the COE since 2014.