1957day.year
The S&P 500 stock market index is introduced, replacing the S&P 90.
The iconic S&P 500 index launches, becoming a key benchmark for the U.S. stock market.
On March 4, 1957, Standard & Poor’s unveiled the S&P 500 stock market index, replacing the earlier S&P 90 measure. Comprising 500 leading U.S. companies across diverse sectors, the new index provided a broader and more accurate gauge of overall market performance. Its market-capitalization weighting quickly made it an essential tool for investors, analysts, and policymakers. Over time, the S&P 500 became the global standard for tracking equity trends and benchmarking investment portfolios. Today, it remains a cornerstone of financial markets, underpinning trillions of dollars in assets worldwide.
1957
S&P 500
stock market index