Rate would be tech startup successes per student. Of course I agree that the rate for academic environments would be greater than zero, and some great companies too.
You're already comparing unlike samples. The base rate for startup success is constrained by ... starting a startup. Folk who rock up to the YC offices are already self-selecting into that group.
I think a better measure would be wealth net wealth at particular intervals -- 5 years, 10 years, 25 years, 50 years.
I was asking for a rate comparison vs YC.