[marcosdumay]

No doubt about that (even then, you will probably want the 90 or 99 percentile, depending on how many interactions you expect a person to have).

Th real median is just very hard to measure, and an easier 99.99 (with more 9's as needed) rank is almost as good.

[jrochkind1]

Can you say more about why you say the "real median" is hard to measure? It doesn't seem hard to measure to me, or any harder than a 99.99 percentile. Why is 50th percentile harder to measure than 99.99th?