The decline in competitive churn is a side effect of the rescue culture that has been growing since the 1980s. Ever since the U.S. Federal Reserve Board stepped in to prop up the market after the 1987 crash, the stock market has grown dramatically from half the size of the U.S. economy to two times larger at its peak in 2020.The number of U.S.
companies that remain in the top 10 from one decade to the next has risen steadily, from just three in 1990 to six at the end of the 2010s. And while churn has weakened in the U.S., it remains relatively robust across much of the world. From the start to the end of the 2010s, just two companies remained on the top 10 list in Japan, four in Europe, four in China and two in the global list, Microsoft Inc.