A recent post by HBR addressed the biased towards young founders in the SV but according to their "quick and dirty" research:
22% of billion USD SV founders were 20-24 at age of founding.
19% 25-29;
22% 30-34,
35% older than 35
2% younger than 20
The better (and more accurate) correlation to examine is: are young founders biased towards YC? I am willing to bet that the majority of applications to YC are from young founders. This is reflected in the people who get accepted.<p>Not to mention I'm surprised you thought you'd ever be able to get a clear answer to such a loaded question on HN.