Also life expectancy changes as you age: http://www.ssa.gov/oact/STATS/table4c6.html http://www.ssa.gov/oact/STATS/table4c6.html By the time you hit 60, you've

Also life expectancy changes as you age: http://www.ssa.gov/oact/STATS/table4c6.html http://www.ssa.gov/oact/STATS/table4c6.html By the time you hit 60, you've gone from ~75 to ~80.