Table3

Binomial Model for Number of Landslides         R.A. Crovelli  
Percent Chance of One or More Landslides During a Specified Time
Mean Recurrence Time (years)
Interval (years) 1 5 10 25 50 100
1 100 100 100 100 100 100
2 50 96.875 99.90234 100 100 100
5 20 67.232 89.26258 99.62221 99.99857 100
10 10 40.951 65.13216 92.82102 99.48462 99.99734
20 5 22.62191 40.12631 72.26104 92.3055 99.40795
50 2 9.60792 18.29272 39.65353 63.58303 86.73804
100 1 4.900995 9.561792 22.21786 39.49939 63.39677
200 0.5 2.475125 4.888987 11.77798 22.16874 39.42296
500 0.2 0.996008 1.982096 4.88182 9.525318 18.14332
1000 0.1 0.499001 0.995512 2.470229 4.879437 9.520785
2000 0.05 0.24975 0.498876 1.242529 2.469619 4.878247
5000 0.02 0.09996 0.19982 0.498802 0.995116 1.980329
10000 0.01 0.04999 0.099955 0.2497 0.498777 0.995066
USA.gov logo