It's 1% multiplied by years of service.
Computation
It is 1.1% if you wait until age 62 to retire. So, it is 30 × (0.011 × 250,000) = $82,500. Also, most of us end up closer to $300,000. I put 30 years but you can substitute 20 if you like. I'll probably work 30 cause I have kids that need education, lol.
I'll hit $300k next year with scheduled step and other raises per the HR compensation projection placed in my personnel folder, and I'm only halfway to retirement. I know psychiatrists at the VA that make both more and less salary than I do. Location matters a lot.
Also, retirement will include TSP and social security not included in the pension. TSP is actually the bulk of a VA employees retirement. It's better retirement than academia 401k in my area, but possibly worse than I could do private practice if I wanted to work harder day to day. Looking at my records it looks like I will be getting about 2/3 of my current income in retirement if I stick with the VA for at least 20 years right now. I'm gradually investing more now that I've gotten the VA to pay off my med school loans.