So conservatively, by market cap it looks like YC is doing 10X on their investment, which is very impressive.
And this is conservatively, since the 3 billion in funding has already been handed out, but some of the companies that have received that funding haven't had a chance to grow and become valuable.
Way better return than that. Assuming they've invested $20k in each company so far (and not including current batch with the new investments but that's fair as there is no return from that) then they've invested $14MM or so for 6% of founders common stock. All that really matters is their ownership of the biggest companies, which will have raised a lot of money, but lets assume they got diluted 2/3rds and own 2% of airbnb/dropbox (I have little feel for how accurate that assumption is). Then the portfolio is worth about $600MM. That's an astonishing 40x return, and it's probably way better than that as we aren't seeing the full returns yet especially from the recent batches (a fairer analysis might be to only include companies 5 years old or something). The analysis I'd really like to see is a cohort analysis showing mean valuation by batch over time, but this might be misleading due to changing market conditions.
And this is conservatively, since the 3 billion in funding has already been handed out, but some of the companies that have received that funding haven't had a chance to grow and become valuable.