You may have noticed that the stock market here in the U.S. has had a rough go of it lately. What you may not have realized is that throughout this decline, the U.S. has increased its share of world stock market cap, because the rest of the world has been falling more than we have. Below is a chart comparing the S&P 500 to the % of world market cap that the U.S. makes up. As of today, U.S. stocks made up more than 37% of world market cap. Earlier this year before China completely fell apart, the U.S. made up less than 34%.