http://www.smashcompany.com/wp-content/uploads/2017/12/Scree...
A few other graphs I collected on my weblog are here:
http://www.smashcompany.com/business/is-it-useful-to-have-a-...
http://www.smashcompany.com/philosophy/do-men-become-warlike...
http://www.smashcompany.com/philosophy/marriage-peaked-in-19...
