Motown, I actually wasn't using the FV function to get my figures, but the FV formula would be: =FV(23%, 23, -2400)
In case anyone wants to know: "23%" is the interest rate, "23" is the number of years (from age 18-40), and "2400" is the amount contributed per year ($100 a paycheck times 24 paychecks a year). From that I get the answer of $1,209,399.88
And then applying 23% to that total gives the $278,161.97 per year amount you'd be earning if you just wanted to take the profits every year and spend it.