Did you look at just the new rich (the people who have gotten rich over the past ten years), or all the rich? If the latter, you're including a lot of dot-com people who wouldn't have gotten nearly as rich if it weren't for the bubble.
I'd have to normalize the data for all kinds of bubbles in a variety of markets, not just the dotcom bubble. Plus, I couldn't see how to determine who was new rich based on the data.
In the light of morning, I'd like to amend my statement to "the expected value for a tech entrepreneur seems to be slightly higher", based on the definition of an expected value:
81 / 400 x 181.77 = 36.80
48 / 400 x 321.47 = 38.57
Given that the odds of making the list in finance are higher, it's still a better bet to start a technology startup.