M2.5 : 21.0 h
M3.0 : 2.89 d
M3.5 : 9.54 d
M4.0 : 31.5 d
M4.5 : 104 d
M5.0 : 343 d
M5.5 : 3.10 y
M6.0 : 10.2 y
M6.5 : 33.8 y
M7.0 : 112 y
M7.5 : 369 y
M8.0 : 1220 y
M8.5 : 4020 y
Based on 362,044 events. Largest M7.9
n = Events per year with magnitude >= M
M <= 8.5
log10(n) = 5.21 - 1.038*M