A stacked mountain chart shows assets under management for U.S. equity index mutual funds and ETFs from 1976 to 2024. The y-axis represents assets in trillions of U.S. dollars, ranging from $0 to $12 trillion. From 1976 until around the year 2000, S&P 500 index funds accounted for virtually all assets under management. After 2000, categories such as U.S. Total Market, U.S. Fund Large Growth, U.S. Sector Equity, U.S. Fund Large Value, and various mid-cap and small-cap blends and growth/value funds began to appear and grow steadily. By 2024, total assets under management surged to nearly $12 trillion. Although S&P 500 funds and U.S. large-cap funds no longer dominate, they still represent a prominent portion of overall assets under management.