1.7% of a low salary
per year up to 20 years then drops to 1% per year thereafter with mandatory retirement at 57. If you go Federal you would be brought in at GS-7 Step 1 probably and then automatic yearly promotions to GS-9. After that you will gain one step per year for steps 1-3. Steps 4-7 are 2 years each and the remainder are 3 year intervals.
One exception to the Salary is the US Park Police... They are on a different pay system due to having Presidential Protection duties which gets them off of the GS pay system.
Municipal/State Retirement= at least
2.5% of a considerably higher salary
Just food for thought if you are the type to look down the road a bit....