Visualization of Fur Affinity, Weasyl, SoFurry, InkBunny & e621 site content by Garek Maxwell.

Data sources:
FA submission map 2015-01-14
FA submission map 2014-04-24
FA submission map 2012-01-11
FA submission map 2011-04-29
FA submission map 2010-04-29
FA submission map 2009-01-27
FA Statistics 2011 (FA forums link no longer active)
FA Statistics - 2014
Weasyl Statistics - (Accessed 12-31-2014)
SoFurry Statistics - (Accessed 12-31-2014, June 2013)
InkBunny Statistics - (Accessed 12-31-2014)
InkBunny Additional Statistics
e621.net - Data sources: Safe/General; Questionable/Mature; Explicit/Adult; Species Tags, In Descending Order
Traffic Statistics, mostly for Weasyl and SoFurry:
http://statstool.com/
http://www.freewebsitereport.org/
http://www.hypestat.com/
https://www.compete.com/