I should add that my figures don't property take into account the ages at which people accumulate the bulk of their net worth. For "number of graduates from top universities" I considered graduates between ages of 22 and 82, but this isn't appropriate, since most people won't acquire most of their wealth until later in life (e.g. the average age of a billionaire is 66), so the prevalence of eventual $30m+ people should be something like 2x what I said, and similarly, for members of the general population (where I included everyone, including children) the prevalence should be something like 3x what I said.
So the actual prevalences of eventual $30+ millionaires should be something like 1 in 1,000 (general population) and 1 in 100 (graduates of top universities).
As for billionaires, there are 442 US billionaires, maybe 100 million in the appropriate age range, so 1 in 250,000 of the general population becomes a billionaire, 129 billionaires at the schools that I looked at with ~250,000 in the appropriate age range, cutting by a factor of 2 to account for possible double counting (undergraduate/graduate), we get a frequency of 1 in 4000 eventually becoming billionaires. (About 0.4 billionaires per university class.)
This analysis is quite crude – one would need the actual age distribution and not just the average age.
What are the chances of being a billionaire or getting $30m plus if you go to Harvard rather than an elite uni?
And then what about HBS rather than Harvard?
[Added: Solipsist made good comments that partially account for the phenomenon, and Douglas_Knight pointed out that the figure of $200m+ below should be $30m+]
This article reports that Harvard has 2,964 alumni worth $200+ million, with a total wealth of $622 billion. These figures are staggering:
Note that Bill Gates "only" has ~$75 billion and that Mark Zuckerberg "only" has ~$30 billion, so that they don't account for Harvard's decisive advantage over other universities.
What is going on here? Why would Harvard come out ahead by such a large margin? Its acceptance rate is smaller than those of Stanford, Yale and Princeton, but by no more than 25%. Moreover, this has been true historically
One can ask a similar question of University of Pennsylvania, which is significantly less selective than Yale and Princeton, but has a decisive advantage over them.
Some possible explanations for the discrepancy:
Regardless of which of these explanations hold, there remains a question of why they would hold.
Is Harvard a better choice than other universities for students who aspire to be wealthy than other top schools?