M2.5 : 6.02 d
M3.0 : 19.5 d
M3.5 : 63.1 d
M4.0 : 204 d
M4.5 : 1.81 y
M5.0 : 15.0 y
M5.5 : 124 y
M6.0 : 1030 y
M6.5 : 8530 y
Based on 3,878 events. Largest M5.6
n = Events per year with magnitude >= M
M <= 4.5
log10(n) = 4.33 - 1.020*M
4.5 <= M <= 6.5log10(n) = 8.01 - 1.837*M