# Return period

From AMS Glossary

## return period

(

*Also called*recurrence interval.) The average time until the next occurrence of a defined event.When the time to the next occurrence has a geometric distribution, the return period is equal to the inverse of probability of the event occurring in the next time period, that is,

*T*= 1/*P*, where*T*is the return period, in number of time intervals, and*P*is the probability of the next event's occurrence in a given time interval.