Wealth manager David Bach: Follow this formula to become a millionaire

Personal finance expert David Bach's formula for becoming a millionaire

According to New York Times-bestselling author and co-founder of AE Wealth Management David Bach, getting rich boils down to a simple formula: Setting aside at least 14 percent of your income.

It's "what the average American has done to become a millionaire by the age of 59 years old," Bach tells CNBC Make It. "You need to be saving 14 percent of your gross income. That's the formula."

14 percent may sound like a lot, but it's the equivalent of just over one hour's worth of income each day, the self-made millionaire points out: "I want you to keep the first hour of the day of your income. So from 9:00 a.m. to 10:00 a.m., that hour goes to you."

Self-made millionaire and bestselling author David Bach
Courtesy of David Bach

Think about it this way, he suggests: "You're going to work 90,000 hours over your lifetime. Most Americans get to the age of 60 and they have nothing to show for it. What you're going to have is at least a million dollars in your retirement account if you pay yourself first, one hour a day of your income."

You may be thinking, "I don't make enough money to save and invest, let alone save and invest 14 percent of my income."

That's "poor thinking," says Bach. "Chances are, you actually do make enough money to be rich — you're just spending it on little things. I call this 'the latte factor.'"

The basic idea of "the latte factor" is that eliminating your $5 daily coffee, or any other regular splurge, could help you save significantly over time.

"I don't know what you're spending small amounts of money on, but I know this: $10 a day can change your life. If you're in your 20s and you start investing $10 a day automatically into your retirement account, at a rate of 8 percent, by the time you hit 60, you've got over a million dollars."

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Writers who take issue with Bach's idea of "the latte factor" argue that it'll take more than giving up small, daily luxuries to save big or really solve financial woes. As Helaine Olen, personal finance expert and author of "Pound Foolish," says, the bigger issue for most Americans is "the fixed costs, the things that are difficult to cut back on. Housing, health care, and education cost the average family 75 percent of their discretionary income in the 2000s."

Still, many people find it helps them gain control over their finances to start with small changes.

More importantly, automate your finances so that 14 percent of your income, for example, goes straight from your paycheck to your retirement savings account. You'll never even see the money you're setting aside and will learn to live without it.

After all, "you can't spend what you don't have in your pocket," says Bach.

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