"There's this new advice out there that 70 is the new retirement age. That is ridiculous," he tells CNBC Make It. "First of all, the life expectancy for men is 76. You want to retire at 70 and have six years left to retire? Ladies, for you, it's 81. You want 11 years in retirement? "
He's responding to an idea popularized by personal finance maven Suze Orman, who, in 2017, wrote on Money: "70 is the new retirement age — not a month or year before." Orman then reiterated that advice to CNBC Make It: Don't retire, or claim Social Security, until you turn 70.
"Let's do the reality check on retiring at 70," says Bach. "The average person in America retires at 62, certainly before 65." There are a few reasons for this, he says: Health issues, less energy or being forced out of the job.
"So let's just get real: Most of you are not going to retire at 70. You're probably going to retire before you're 65."
Research backs up his claim: A survey from the Employee Benefit Research Institute found that, while nearly four in 10 workers expect to work until age 70, only 4 percent of retirees report being able to work that long.
"I'm not against working until you're 70," says Bach. "If you love what you're doing and you can keep up until you're 70, fantastic. I know people who work in their 80s. Great, if you can. … But don't assume that you've got an extra decade right now to save money because somebody else told you 70 is the new 60."
Rather than planning on working longer to set yourself up for your golden years, start saving more money now, he says: "The way you get the best return on retirement — I call this ROR — is you save, save, save, save, save … And you retire in your early 60s, able to afford it, and then you really go have the best years of your life."
Settling down in your 60s means "having the energy to finally do what you want to do when you want to do it," says Bach. "Will you have energy at 75? Yes, you will. But guess what? It won't be the same as you do when you're 65. Sixty to 75 are the 'go go years' in retirement; 75 to 85, it's the 'slower go' years; 85 to 100, it's often the 'won't go' years."
To ensure you're not working during the "slower go years" or the "won't go years," follow this formula to figure out how much you should have saved at every age in order to set yourself up for a comfortable retirement.
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