1. I'm sure compounded returns would be nice to do, but you don't know the start date for any of those investments. A 2004 vintage fund does not mean the investments are from 2004. Instead, it means the fund made it's first investment in 2004 and will continue deploying money over ~7-8 years.
2. In the VC industry, a wipeout is a wipeout. Call it Zero, not 0.5x.
3. LPs care more about cash-on-cash multiples, not compounded returns (aka IRR). There's an expression that will help explain this point: "You can't eat IRR." VC is a 10-year horizon business and GPs call do special moves to improve the IRR (calling down capital as needed, and then returned capital upon exit even if it's going to be called down again and reinvested). But, at the end of the day, the best measure of the success of any fund is the gross cash-on-cash multiple of the entire fund.