The least affluent families had the largest declines. Average incomes dropped by 8 percent for the bottom 20 percent of families, the Fed reported in its triennial Survey of Consumer Finances, one of the most comprehensive sources of data on the financial health of US families.

For the most affluent 10 percent of US families, average incomes rose by 10 percent from 2010 to 2013. For the rest of the population, average incomes were flat or falling.

WASHINGTON — Economic growth since the Great Recession has improved the fortunes of the most affluent Americans even as the incomes and wealth of most US families continues to decline, the Federal Reserve said Thursday.


The new report, broadly consistent with other data on the aftermath of the Great Recession, underscores why so many Americans think the economy remains in poor health.

While the pie has grown, most people are getting smaller slices.

The result is that wealth also is increasingly concentrated. While overall wealth barely changed during the survey period, the money shifted from the bottom toward the top. For the top 10 percent of families, ranked by income, estimated average wealth increased by 2 percent to $3.3 million. For the bottom 20 percent of families, average wealth sharply declined by 21 percent to $65,000.

There is growing evidence that inequality may be weighing on economic growth by keeping money disproportionately in the hands of those who already have so much they are less inclined to spend it.

President Obama last year described income inequality as “the defining challenge of our time.”

The Fed’s chairwoman, Janet L. Yellen, said earlier this year it was “one of the most important issues and one of the most disturbing trends facing the nation.”