About 93% of U.S. households' stock market wealth is held by the top 10%.

Why it matters: This stat — first spotted in the FT — is a crucial bit of context to keep in mind amid the heavily hyped surge of smaller retail investors who flocked to the stock market during and after the COVID crisis.

Details: While it's true that a record high 58% of American households do own stocks via mutual funds or as individual shares, in the aggregate the amount of stock most of these folks own is tiny.

The big picture: Despite the trauma of the last few years — the collapse of stocks in the early days of the pandemic, and the brutal bear market brought on by the Fed's rate hikes over the last couple of years — the stock market has soared over the long term.

• In the last 10 years, the S&P 500 gained 155%, and the tech-heavy Nasdaq rose a whopping 250%.

Between the lines: While bullish surges like those are welcome to pretty much all investors, the fact is that the majority of the gains go to the richest stockholders.

• "Stock market booms primarily boost the wealth of households at the top of the wealth distribution, as their portfolios are dominated by listed and unlisted business equity," wrote three academics who studied long-term trends in wealth inequality in the U.S., in a 2020 article published in the Journal of Political Economy.

The bottom line: The U.S. market is simultaneously at its most unequal point on record — and the most democratized.

Editor's note: This story and chart were corrected to reflect that it is 93% of U.S. households' stock market wealth (not 93% of the stock market) that is held by the wealthiest 10% of those households.