Studies have shown that active fund managers routinely underperform the S&P500 index*​

The 10 Worst Days in the S&P 500 (1957–2026)

The 10 Worst One-Day Declines in the S&P 500 Index (1957-2026) Here are the 10 largest single-day percentage declines in the S&P 500 over the 69-year period, ranked by severity: Takeaways: