Given the high percentage of startups that fail, I wonder what percentage of VC funds fail, where perhaps we can define fail as "return less than the S&P 500 ov

Given the high percentage of startups that fail, I wonder what percentage of VC funds fail, where perhaps we can define fail as "return less than the S&P 500 over the same timeframe". I imagine the true answer is a much more difficult number to come by. Easier to get late money in a successful company and claim "qualitative success".