In general, 50% of American businesses fail during the first five years. (I was told that quite a long time ago; I don't know the current figure.)

Go have a look at the websites of some venture firms. At least them list all of the portfolio companies they've ever had, even if they've exited. Now look into whether those companies failed, were acquired, whether the IPO worked out well and so on.

That's going to be a lot of work but would be valuable information for everyone to know. If you wrote up on article about it on your site, you'd get lots of readers, inbound links, maybe press coverage.