The numbers would be around 95% or higher, if you go to the NCAA site and do the math it might be closer to 97%. So when I hear that a player chooses not to play soccer to focus on there studies I scratch my head due to the fact that a soccer player playing college soccer has an almost 100% chance of graduating compared to a normal student. Most athletic departments have so many checks and balances you would have to work very hard to fail out of school, it's almost impossible.
Like anything there are always exceptions to the rule.