Today the S&P 500 had the 8th largest daily percentage gain (+9.52%), largest daily point gain (+474.13), and largest intraday point swing (+532.91) in history

List of largest daily changes in the S&P 500 Index:

• Largest percentage changes: https://en.wikipedia.org/wiki/List_of_largest_daily_changes_in_the_S%26P_500_Index#Largest_percentage_changes
• Largest closing point changes: https://en.wikipedia.org/wiki/List_of_largest_daily_changes_in_the_S%26P_500_Index#Largest_closing_point_changes
• Largest intraday point swings: https://en.wikipedia.org/wiki/List_of_largest_daily_changes_in_the_S%26P_500_Index#Largest_intraday_point_swings

The 7 daily percentage gains larger than today all happened during the 1929 great depression (+16.61%) and 2008 financial crisis/great recession (+11.58%).