A new report from the New York Federal Reserve shows older Americans have been ramping up their debt while younger Americans have not.

In real terms, debt in the hands of Americans between 50 and 80 years of age has increased by 59% since 2003. At the same time, the aggregate debt of those age 39 has dropped by 12%, the report released Friday shows.

The New York Fed report examines why. Mostly it’s a function of the housing boom and bust.

Home-secured debt, per capita, has surged 47% for those age 65, for an increase of $11,191, while it’s dropped 28% to $8,195 for those aged 30.

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That makes sense as older Americans with a home, facing declining prices after the housing market collapsed but also declining interest rates, refinanced. At the same time, younger Americans were less able to get on the housing ladder, either because they didn’t want to since their job prospects were diminished and they were struggling with student debt, or they couldn’t because banks had made lending more difficult.

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That same trend played out for auto loans as well — on a per-capita basis, auto debt is up 29% for those 65 years old, but it’s down 6% for those 30 years old.

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Student debt is for the first time becoming an issue at age 65, surging 886% (though it’s still rare.) Meanwhile, 30-year-olds have seen a 174% increase in student debt per capita.

The New York Fed report stresses that the rising debt for older Americans isn’t necessarily a bad thing — from a separate survey, they note the net worth of households with heads aged 65 or older is similar in 2013 and 2004 and 2007, so the rising debt is balanced by rising assets. The other point is retirement-aged consumers historically repay their debts at higher rates than younger borrowers.

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But the report notes that the more muted borrowing of younger consumers has consequences, in particular as they are less able to get on the housing ladder and build wealth.