S&P 500 Market Cap Tops $40 Trillion By: TalkMarkets October 18, 2021 at 13:13 PM EDT The S&P 500’s market cap has increased by more than $6 trillion this year, leaving the index’s total market cap above $40 trillion. Read More >> Related Stocks: Alphabet-A Amazon.com Apple Berkshire Hathaway Facebook JPMorgan Chase & Co Microsoft NVIDIA Corp SPX Tesla, Inc. Visa