Recurrence Interval and Annual Probability Recurrence Interval also referred to as return period is the length of time between the occurrence of an event. We can define recurrence interval (RI) as the number of years in the record (N) divided by the number of events (n): RI = N / n Annual Probability is the probability that an event will occur in any given year. We can define probability (AP) as the inverse of the recurrence interval: AP = 1/RI Question at position 5 5 5 points Question at position 5 As described in the previous question, 15 major earthquakes with magnitude > 7 have occurred in California in the past 212 years. Given the recurrence interval, what is the likelihood or probability that a major earthquake will occur in California this year? As described in the previous question, 15 major earthquakes with magnitude > 7 have occurred in California in the past 212 years. Given the recurrence interval, what is the likelihood or probability that a major earthquake will occur in California this year? 0.14 or 14% 0.07 or 7% 0.01 or 1% 0.12 or 12%