I honestly don't know, and at this point it would be digging through almost 100 years of legislative patches to find the current state. From what I read, they'

I honestly don't know, and at this point it would be digging through almost 100 years of legislative patches to find the current state. From what I read, they'd basically converged its cost of living and payouts to be Social Security-equivalent (and tied to it for the future), but I believe it's still a distinct program (that just happens to pay the same amount). There were also some oddities with porting between the two systems (railroad work -> social security work, or vice versa). It stuck in my mind because the idea of a government-backed retirement system before social security seemed such a weird historical quirk!