The S&P 500 is up 12% in 2026, driven largely by enthusiasm for AI, but both it and the Nasdaq Composite have recently fallen sharply amid sticky inflation, elevated bond yields and concerns over how AI is being financed. The CAPE ratio is around 41, more than double its historical average of 17.8, and in 155 years of data only the dot-com bubble saw it stay above 40 for a sustained period, peaking near 44 in December 1999. The Buffett indicator sits around 237%, but the author argues this may overstate valuations because many S&P 500 companies earn revenue overseas that is not counted in U.S. GDP. Both metrics point to weaker future returns, though neither signals when a correction will come; the author argues that selling everything over high valuations would mean missing long-term gains, and that this is a chance to reassess portfolio risk and consider trimming outsized exposure to AI or speculative tech stocks.
Summary written by Upside AI from the original article. Read the source for full details.
Original headline: The Stock Market Sounds an Alarm for the First Time in Nearly 27 Years . Here Is What History Says the S & P 500 Will Do Next .
Read the original on fool.com ↗
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S&P 500SPYvaluationartificial intelligenceWarren Buffett
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SPY
▼ Likely negativeSPDR S&P 500 ETF
Relevance: medium
| Market | US stocks |
|---|---|
| Sector | ETF |
| Close on 10/22/2026 | 763.96 |
| Change that session | -1.18% |
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