The No. 1 thing that can improve the retirement security of older workers

Ready for today’s retirement investing pop quiz? What’s the single most consequential thing you can do to improve your chances of not running out of money in retirement? I’ll try answering this question in a minute, but I’ll note first that chances are good that this question isn’t just hypothetical but applies to you personally. A just-released survey of retirees suggests that the vast majority of near-retirees are in dire financial straits.