What is S&P 500?

The S&P 500 is a stock market index tracking 500 large-cap U.S. companies. Commentary focuses on its valuation, concentration, earnings dynamics, and breadth as of mid-2026.

• Mar 2026 - Howard Marks said that buying the S&P when its P/E ratio was 23 historically yielded 10-year annualized returns between +2% and -2% with no exceptions.
• Apr 2026 - Josh Brown said that 45% of the entire S&P 500’s growth came from Micron and Nvidia.
• May 2026 - James Lavish noted that the top 10 S&P 500 companies now have over a 40% share, exceeding the 28% at the dot-com peak.
• May 2026 - Andy Constan stated that 62.5% of all year-over-year earnings changes accrue to AI stocks, and that the S&P’s expected total earnings of $400 billion raise questions about GDP support.
• Jun 2026 - Neil Dutta reported that 15 non-tech S&P 500 companies worth $2 trillion now move with semiconductors at correlations of 0.5 or higher, 12 of which are industrials.
• Jun 2026 - Rajiv Jain said that utilities offer 8-10% EPS growth over 5-10 years, faster than the S&P’s 8% last decade.
• Jun 2026 - Josh Brown noted that 40% of S&P stocks were negative on the year, and earnings for most companies are below where they were at the start of this bull market.