Does anyone know of a "calculator" similar to the one linked above that shows your worldwide rank in terms of net worth AND allows negative net worth? (I will gladly accept a table instead of a calculator.)

Bafflingly, http://www.globalrichlist.com/wealth silently converts negative numbers into their absolute values, resulting in ridiculous claims. (For example, an underwater home equity of -100000 USD is interpreted as 100000 USD.)

an extremely powerful calculator

Here it is.

(If your after-tax family income is $100k, for a 2-adult 0-child family in the US then you're in the top 0.8% before giving 10% and the top 1.0% after, and this is alleged to be equivalent to saving 3 lives per year. Make it $50k/year and it's top 3.9% -> top 4.7% and 1 life per year. In the other direction, at $200k/year it's top 0.1% -> top 0.1% and 6 lives. I don't know how compelling those numbers would be to the people they're relevant to. For the avoidance of doubt, I am able to halve and double the number 3, but rounding could have affected the figures a little.)

I have a bit of an uneasy feeling about comparing your wealth percentile before and after. It rather gives the impression that your reason for wanting to earn more is to be ahead of as much of the population as possible. Which I suppose it is, to some extent for most people, but it seems like it shouldn't and it's unfortunate to be encouraging that mode of thinking.

(I guess that the actual intended thought process is less "well, OK, I'll still be in the top 0.6%, which is good enough for me, so I'll go ahead and donate" but "well, I suppose it's kinda indecent to begrudge a bit of my income when even after donating I'll be in such a privileged position in global terms" -- which isn't quite so bad, but still doesn't seem like how anyone ought to be thinking about their income.)