[fbbwsa]

you are correct, I skimmed/misread the post. I thought it 75 richest LIVING people (and could not for the life of me figure out why they were using such an old Forbes list...), not in history.

Thats why I was assuming we could assume dead people and those under 25 wouldn't be as relevant and fit all potential candidates to a 50-ish year birth-year block.

Taking any arbitrary 9 year period in a 50 year period and finding that it captured ~20% didn't seem odd to me, which is why I screwed up with my bad argument.

Good catch.