# Probability of Poisson distributed outcome over *multiple* time periods

I have been working with the Poisson distribution to calculate the probability of events occuring in a given time period (1 day). I now need to calculate the probability of an event occurring over multiples of this time period (in a year), and I'm not sure how to go about this.

Can anyone give me a pointer as to what techniques I should research to be able to do extend my analysis from one time period to many?

• Here is a work that examines many locations of nuclear facilities for a specific time interval with respect to the failure of backup cooling system to engage across facilities available at osti.gov/servlets/purl/10191309 . However, the modeling may also be appropriately viewed as a many year analysis at the same facility with each year independently modeled. Dec 11, 2020 at 5:38