American households are continuing to improve financially, according to Hearts & Wallets, a data source on finances and investing.

Fewer U.S. households are in the lowest asset group of under $50,000 in investable assets, according to a report released Thursday by the organization. This group declined by 2.1 million since 2013, dropping from 77.2 million to 75.1 million, even as the total number of U.S. households increased by 3.5 million to 126 million.

The number of households with $5 million or more in investable assets increased by 50 percent, from 900,000 to 1.4 million, during that same time period, Hearts & Wallets said in its report, which partly relied on Federal Reserve data.

“The really exciting news for American families is the progress made at the lower end of the investable asset spectrum,” said Laura Varas, CEO and founder of Hearts & Wallets, in a statement. “To grow wealth from a small asset base takes a lot of work, and these families are succeeding through a combination of savings and a small assist from the capital markets.

U.S. households have increased their investable assets each year since the Great Recession of 2008 and now control $48.4 trillion, an increase of 40 percent over the last five years, the study said.