For simplicity, view a retirement benefit as pieces of a puzzle. The first piece we consider is the length of service. Then we calculate the high-five average salary. We take these two pieces and apply it to a benefit formula to determine the retirement benefit.
Other factors that determine the monthly benefit are the retirement age and the survivor benefit option selected at retirement.
To learn more about how the retirement benefit is calculated, see:
View this short video to learn how your monthly retirement benefit is calculated