The Shrinking Public Market

For most of the twentieth century, the public stock market was where the economy's growth showed up. A company grew, went public early, and the ordinary investor rode the expansion from there. That arrangement quietly ended, and the evidence is a single startling fact: the number of companies listed on U.S. exchanges has roughly halved since the mid-1990s, from around eight thousand to near four thousand.

That is not a statistical curiosity. It changes what you are buying when you buy the market. The public market has become smaller, older, and more concentrated, and the growth that used to happen in public view now happens in private hands. If your entire equity exposure is a public index, you should understand what that index no longer contains.

Fewer Companies, and Older Ones

The halving of the public company count is one of the most important and least discussed facts in modern markets. Alongside it, the companies that do go public are far older than they used to be. Where a technology company once listed a few years after founding, it now often waits a decade or more, going public as a mature business rather than an emerging one.

Put those two facts together and the picture is clear. There are fewer public companies, and the ones that remain are, on average, larger and later in their lives. The exchange is no longer the on-ramp to growth. It is closer to a retirement home for companies that already did their growing somewhere you could not invest.