How Did the U.S. Stock Market Get So Old?
Companies are already grown up when they go public, and big corporations like Amazon keep swallowing younger competitors.
Illustration: Woshibai for Bloomberg Businessweek
Certain adjectives come to mind in describing the U.S. stock market. Sprawling. Resilient. Diverse. Here’s another you probably haven’t thought of: old. Thanks to an absence of new entrants, the average age of companies listed on American exchanges has been steadily rising for three decades. Now it’s 20 years, almost twice the average in 1997, during the dot-com craze.
The market won’t be getting much younger this year. Six unicorn tech giants, including ride-sharing network Uber Technologies Inc. and online home-rental service Airbnb Inc., are preparing to go public at an average age that’s four years older than what was typical two decades ago.