Distributed swarm statisticians ...
Could certainly make use of statistics gahtered by Nationmaster : http://www.nationmaster.com/
Hmmm, there's something weird about the way taxation data is calculated [here. http://www.nationmaster.com/graph-T/eco_bud_rev_cap here].] I'm sure it's right, but it's a funny way of looking at it.
DanielDavies warns against the DataPollution
Optimaes attempts to build a maths mob to investigate alternative economics