Households are wealthier than ever. But if you're a Millennial or have a low credit score, you probably don't feel any richer.

Since the financial crisis, home equity has grown for older Americans as home prices have recovered and debt has accumulated more slowly, according to a study by the Federal Reserve Bank of New York released Thursday.

But younger people and borrowers considered less creditworthy haven't reaped the same benefits. Homeownership has declined for these Americans because of tighter lending standards.

The Fed study examined home equity between 2006 and 2017.

In 2006, before the crisis, Americans over age 60 and under age 45 each held about a quarter of the country's overall home equity.

But by 2017, older Americans held 41% and younger Americans just 14%. That's partly because of the aging population, but also because of tougher mortgage standards and higher student loan debt, the researchers said.

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"Tight credit can limit the scope for renters to become owners and for current homeowners to access their equity," said Beverly Hirtle, executive vice president and director of research at the New York Fed.

The shift in housing wealth distribution could have long-term effects on the nation's housing cycle, the New York Fed researchers warned. It also leaves far less cushion for those younger Americans or low-credit-score borrowers in harder financial times.

In times of hardship, homeowners can use a portion of the equity they've accumulated in their homes to bridge financial shortfalls. Equity is the difference between the value of your home and how much you owe on your mortgage.

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"The distribution is important, as it reflects who will likely bear the burden when the next economic downturn occurs," Hirtle said.

The findings were part of the New York Fed's household debt report, which showed that American households carried $13.21 trillion in debt in the first quarter, up 0.5% from the fourth quarter of last year.

Americans are also doing a better job paying off credit card balances, and the delinquency rate of their mortgages has continued to improve, according to the report.