Historical analysis doesn't have enough comparable data points and there are significant failures on record. How many times has a reactor been hit with an 8.9 m

Historical analysis doesn't have enough comparable data points and there are significant failures on record. How many times has a reactor been hit with an 8.9 magnitude earthquake and a tsunami? There's only 1 data point. Historical and simulation models both have large negative expected value (unless you can rule out a black swan event with a miniscule probability at around 10^-8 - unattainable certainty with current analysis).