The U.S.’s historic economic expansion has so enriched one-percenters they now hold almost as much wealth as the middle- and upper-middle classes combined.

The top 1% of American households have enjoyed huge returns in the stock market in the past decade, to the point that they now control more than half of the equity in U.S. public and private companies, according to data from the Federal Reserve. Those fat portfolios have America’s elite gobbling up an ever-bigger piece of the pie.

The very richest had assets of about $35.4 trillion in the second quarter, or just shy of the $36.9 trillion held by the tens of millions of people who make up the 50th percentile to the 90th percentile of Americans — much of the middle and upper-middle classes.

Chalk up at least part of their good fortune to interest rates, said Stephen Colavito, chief market strategist at Lakeview Capital Partners, an Atlanta-based investment firm for high-net-worth investors. People can’t get much of a return on certificates of deposits and other passive investments, so they’ve pumped money into stocks and […]