Money

This is the age when Americans are deepest in debt

Millennials between the ages of 25 and 34 have an average of $42,000 each in personal debt, excluding home mortgages, according to Northwestern Mutual's 2018 Planning & Progress Study. The findings are based on a survey of over 2,000 U.S. adults, including an oversampling of more than 600 millennials (defined here as those aged 18-34).

That's higher than any other generation surveyed. But it might not be a problem. "In my experience, young people don't break in to positive net worth until their early to mid-30's, and that's okay," Oklahoma City-based financial planner Amy Hubble tells CNBC Make It.

Between the ages of 25 and 34, adults often take on debt to get settled; they consider buying homes and starting families. On top of that, many millennials are also paying down student loans, which adds to their burden, Hubble says.

Gen-Xers and baby boomers, meanwhile, who may have older or grown-up children, have "finally got some equity built up in their homes, so while they typically still hold some debt on major items, it's not as large a concern," Hubble says. Plus, older generations may have used inheritances to help pay down some of their remaining debt.

Credit card balances make up a full quarter of what the average older millennial owes, while student debt accounts for about 16 percent, according to Northwestern Mutual.

Millennials are "inundated with credit card offers," Virginia-based financial planner Russell Robertson tells CNBC Make It. "It's relatively easy to get instant credit. We are surrounded about advertisements on how to get cash now."

"In my experience, young people don't break in to positive net worth until their early to mid-30's, and that's okay." -Amy Hubble, financial planner

Attitude and mindset may also play a role in their accumulating debt, Cleveland-based financial planner Michael Kelley tells CNBC Make It. Unlike other generations, millennials have not faced major financial crises that have required them to develop their scrimping and saving skills. "Older millennials are now two generations away from those raised during the Great Depression. Their family isn't talking about how tough it was to wait in a soup line," he says.

Many of those aged 25 to 34 have already forgotten about the Great Recession, too, because they were still in college or had just started their career, Kelley says. "They probably didn't have a mortgage or a family to take care of so it didn't impact them the way it impacted their parents and grandparents," he adds. "Not to mention, with the help of Amazon, you don't even need to leave the house to rack up the debt."

Financial planners believe that, with the right approach, older millennials can still pay down debt and get to a financial place that's more similar to other generations. As St. Louis-based financial advisor Peter Lazaroff tells CNBC Make It, "People over the age of 35 have had more time to pay off debt and tend to earn more than the younger 25-34 year old workers."

Also millennials haven't yet hit their earnings peak. Pay continues to rise for college-educated men until age 49, generally, and for college-educated women until age 40, according to compensation research firm PayScale.

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