What is S&P 500?
S&P 500
The S&P 500 is a stock market index tracking 500 large U.S. companies. Through mid-2026, commentary centers on valuation, concentration, earnings, and breadth, with AI’s outsized influence a growing theme.
How it developed
- Jul 2026 – Jeff Currie said energy is about 3% of the S&P, needing 10-15% for a super cycle, implying AI overvaluation. Nathaniel Whittemore reported J.P. Morgan analysts’ claim that since late 2022, AI drove 75% of S&P returns, 80% of earnings growth, and 90% of capital spending growth. Barry Knapp cut tech exposure to 25% versus the index’s 37%.
- Aug 2026 – Victor Haghani warned that 25% earnings growth for 3-4 years could push corporate earnings to 50% of GDP, versus a 6-8% norm. Michael Batnick observed six of the eight years with the top 10 stocks contributing most have occurred since 2020. Ed Yardeni’s firm moved tech and communication services to market weight. Jared Dillian argued index funds aren’t safe, citing 1929’s 89% drawdown.
- Aug 2026 – Michael Batnick said forward PE fell from 29 to 22 while stocks rose almost 70%. Michael Santoli noted forward price-to-free-cash-flow is 30. Ben Carlson said the top 10’s market cap weight is 11%, below the 18% average since 1990. Santoli added that all outperformance occurred in calendar 2020.
In the evidence
Every line below is attributed to a named speaker.
Barry Knapp holds tech at 25% of portfolio versus the S&P 500 index weight of 37%, a 12-percentage-point underweight.
“I've reduced my exposure to the technology sector. The index weight is 37%. I'm at 25.”Barry Knapp · 29 Jul 2026
Every historical instance of buying the S&P 500 at a P/E of 23 produced annualized 10-year returns between +2% and -2%, with no exceptions.
“If you bought the S&P when the P/E ratio was 23 in every case there were no exceptions. In every case, your annualized return over the next 10 years was between two and minus two.”Howard Marks · 25 Mar 2026
Howard Marks on buying the S&P 500 at a P/E of 23 and the guaranteed range of 10-year returns.
“If you bought the S&P when the P/E ratio was 23 in every case there were no exceptions. In every case, your annualized return over the next 10 years was between two and minus two.”Howard Marks · 25 Mar 2026
Tech stocks rose nearly 70% since January 2025 while the sector's forward P/E compressed from 29 to 22, indicating earnings growth rather than multiple expansion drove the rally.
“In that time the forward PE has gone from 29 to 22 while the stocks have risen almost 70%.”Michael Batnick · 19 Aug 2026
Goldman Sachs estimates systematic CTAs could sell roughly $31 billion globally over one week, rising to as much as $184 billion over one month, if the S&P 500 decline hits additional trend-level triggers.
“Goldman estimates that they could sell roughly 31 billion globally in a down tape over the next week rising to as much as 184 billion over the next month if the decline continues through additional trend level triggers.”Jim Bianco · 30 Jul 2026
Goldman Sachs estimates systematic selling of roughly $31 billion globally over the next week, rising to as much as $184 billion over the next month, if the S&P 500 decline continues through additional trend level triggers.
“Goldman estimates that they could sell roughly 31 billion globally in a down tape over the next week rising to as much as 184 billion over the next month if the decline continues through additional trend level triggers.”Jim Bianco · 30 Jul 2026
Barry Knapp states his underweight tech position in one line.
“I've reduced my exposure to the technology sector. The index weight is 37%. I'm at 25.”Barry Knapp · 29 Jul 2026
Andy Constan on where the AI overvaluation actually lives.
“It's not the P that's the bubble, it's the E.”Andy Constan · 16 May 2026
The NASDAQ 100 is up nearly 650% over the past 10 years, surpassing the Dow in the 1920s, the S&P 500 in the 1950s, and Japan's Nikkei in the 1980s.
“The NASDAQ 100 now over the past 10 years is up nearly 650%. Higher than the Dow of the 20s, higher than the S&P in the '50s, higher than Japan in the 80s.”Michael Batnick · 13 May 2026
The S&P 500 trades at 30x forward free cash flow, versus the more commonly cited 23x forward earnings, making valuations look considerably less attractive on a cash basis.
“Actually, on a forward price to free cash flow basis, we're at 30 in the S&P.”Michael Santoli · 21 Aug 2026