What this data shows is G Major truly is the "people's key." For those not familiar with music a 12 bar blues uses 3 chords: the so-called I, IV, and V chords (the first, fourth, and fifth chords in the key). In the key of G that would be G (I), C (IV), and D (V). Look at the most popular chords. Instead of analyzing by chords I would have analyzed by key - what keys do you need? Convention says G Major is the "peopl…
(Many of the other options include either B major or F major in the I/IV/V, and those are considerably more difficult to play)