4d6 Probability Curve

D&D and AD&D players have been predominantly using the ability-score generation method of "roll 4d6, drop the lowest die" ever since the AD&D 1st Edition Dungeon Master's Guide specified it as "Method I" in 1979. However, I've never seen a graph of the probability curve for this method, so I figured I'd create one and present it below.



For good measure, in case someone needs the exact numbers involved, I've included those on the following table:

Result 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Total
Count 1 4 10 21 38 62 91 122 148 167 172 160 131 94 54 21 1,296
Percent 0% 0% 1% 2% 3% 5% 7% 9% 11% 13% 13% 12% 10% 7% 4% 2% 100%