[Superman]

Defined benefit pension plans do create a future liability, and so they are required to be reviewed by an actuary each year. The actuary determines the amount the company must set aside to cover the expected obligations. In other words, they are largely "pre-funded." The money earns interest, which is calculated into the actuary's figures. Folks have certain expected retirement dates and ages, and certain life expentancies. Again, this is what actuaries deal with. Federal law requires that these funds be signed off by an independent actuary annually. You wanna make obscene money, become an actuary. I considered it and decided not to. If I had, I'd be much richer, but I wouldn't be having this much fun.