Here is an example of retirement planning (using today's dollars - no inflation), Provide your own or hypothetical example and see what you get. Respond to one other Income $100,000/year, save $10,000/year and invest at 3% to retire in 30 years. At retirement time will have about $475K ($560K if the rate is 4%). (FV = ? PV = 0, PMT = 10K, I/Y = 3, n=30) If this person wants the money to last 30 more years, they can withdraw $28K annually (PMT = ?, PV = $475K (or $560K), n=30, fv = 0)