The S&P 500’s Biggest Strength Is Now Its Biggest Risk

For more than a decade, buying the S&P 500 Index ($SPX) has been one of the simplest and most effective ways for investors to build wealth. The strategy required little effort, low fees, and plenty of patience. Those who stayed invested through market swings were rewarded with one of the strongest bull markets in history.

Yet success can create its own challenges. As trillions of dollars continue flowing into a handful of index funds, market concentration is reaching levels few investors have seen before. The S&P 500 remains a powerful long-term investment vehicle, but the numbers suggest investors should understand what they actually own as well as the risks that come with it.