The stock market enriches a minority and impoverishes the rest: 100 years of data prove it

For nearly a century, U.S. markets have produced $91 trillion in shareholder wealth. Yet this value creation rests almost entirely on a handful of companies. A study conducted by economist Hendrik Bessembinder on nearly 30,000 stocks listed between 1926 and 2025 shows that only 46 companies account for half of the gains generated on Wall Street. Behind the historical performances of American indices, the reality of the market appears much more unbalanced than it appears.

46 companies captured most of Wall Street's gains

The study reveals that the American stock market has generated approximately $91 trillion in net shareholder wealth over a century. Yet, “only forty-six companies captured half of the net wealth created for shareholders”.

This spectacular concentration overturns the idea of ​​a market driven collectively by thousands of companies. In fact, a handful of companies captured an overwhelming share of the overall performance. Hendrik Bessembinder reminds also “that around 60% of stocks have, over their stock market life, done less well than short-term government securities”. In other words, the majority of listed securities did not even outperform investments considered to be low risk.

The figures put forward by the study illustrate the extent of the phenomenon:

• $91 trillion in net wealth was created by U.S. stocks between 1926 and 2025;
• Only 46 companies account for half of this value creation;
• 60% of US stocks have underperformed Treasury bonds over their trading period;
• 1 dollar invested in American stocks would have become almost 15,000 dollars, compared to only 25 dollars for short-term Treasury bills;
• Groups like Altria or IBM are among the main historical creators of stock market wealth.

This aggregate performance, however, masks a massive asymmetry between winners and losers. The observed dynamic is largely based on companies capable of sustainably maintaining their economic domination thanks to scale effects, monopolistic positions or a technological advance that is difficult to catch up with.

Why does this study weaken active management and strengthen ETFs?

The study reveals the structural limits of active management. Since most of the stock market's performance comes from an extremely small number of stocks, missing these few winners immediately becomes penalizing for fund managers. The slightest underexposure to these behemoths is immediately paid for in relative performance.

This imbalance partly explains why many active funds fail to beat the major stock indices over the long term. SPIVA data show that approximately 80% of US large-cap funds underperform the S&P 500 over one year, while more than 85% fail to beat it over periods of ten to fifteen years.

This reality mechanically fuels the rise of ETFs and passive strategies. Cap-weighted indices automatically increase exposure to dominant companies as they increase in value. Investors thus capture the performance of the big winners without having to identify them in advance. This logic is increasingly reminiscent of certain behaviors observed in crypto markets, where a few assets concentrate most of the flows and performances while a multitude of tokens gradually disappear from the circulation of institutional investors.

The publication of this study rekindles the debate around the growing concentration of global financial markets. Between the domination of technological giants, the massive growth of ETFs and the persistent difficulties of managers in beating benchmark indices, the entire traditional mechanism of stock selection finds itself weakened. For stock market investors, the challenge no longer consists only of identifying the next nugget before the market, but above all of maintaining sufficient exposure to the rare companies capable of sustainably capturing global value creation.