Interesting graphic. Links?
Also: My colour-blind son would like a word with the person who picked a red-to-green colour scale. In case anyone is wondering what a good alternative is: different shades of the same colour work great for most colour-blind people.
ETA: about one-in-ten men are colour-blind to some degree. The condition is much rarer in women. I used to think it was rare overall, but nope, it’s pretty common.
