Instead of relying on one withdrawal rate, says Vanguard's Maria Bruno, "be flexible and make adjustments along the way."
When markets do well, you could take out 5% or 6%. In down times for stocks, dial back. Once a year, sit down with a calculator -- try the Fidelity Income Strategy Evaluator at Fidelity.com -- and come up with a safe withdrawal amount based on your expenses and your portfolio's performance.
