This is from Cavalli-Sforze et al. 1988. Your interpretation, Jordan, is correct. However, 0.2 is not a percentage, it is Nei's genetic distance. See https://en.wikipedia.org/wiki/Genetic_distance … for its definition. This was based on 120 allele variants only.
It's Fst methinks. Modern studies give about the same result, though I didn't find a big matrix of distances when I asked.https://twitter.com/KirkegaardEmil/status/940682909312266240 …
