M2.5 : 19.4 h
M3.0 : 2.52 d
M3.5 : 7.87 d
M4.0 : 24.6 d
M4.5 : 76.9 d
M5.0 : 240 d
M5.5 : 2.06 y
M6.0 : 6.42 y
M6.5 : 20.1 y
M7.0 : 62.7 y
M7.5 : 196 y
M8.0 : 613 y
Based on 611 events. Largest M6.8
n = Events per year with magnitude >= M
M <= 8.0
log10(n) = 5.13 - 0.990*M