I have not seen hard numbers. But looking at Class of 2023 RD thread, it looks like most deferred kids were ultimately waitlisted. Not sure how self selecting those reports are though. .
The pressure is certainly on in the deferral letter to convert to ED2, which my s20 will not be doing. With his stats, he has two nice merit packages already. He really likes Case and would have attended if he’d gotten comparable aid (his grandparents and cousin attended). But ED2 locks him into possibly full pay.
Very unethical to defer a kid and say— but we’ll probably accept you if you commit to ED. The alums in our family are horrified Case would do this.
On to other options!