Table 3 Frequency of occurrence of a given number of events at return periods 100 – +10000 based on a sample of three different time periods: 50, 100, and 200 years. Total length of sample 15000 years.

Number of events in each class of return period Return period (years)
1 2 3 4 1 2 3 1 2 3 1 2 3
300, 50 year periods 78 25 4 1 17 2 – 21 2 – 1 1 –
150, 100 year periods 54 26 10 2 15 3 – 17 4 – 1 1 –
75, 200 year periods 23 19 5 9 10 4 1 11 7 – 1 1 –