The S&P 500 Shiller CAPE ratio is above 40, and that puts the stock market crash debate back on a rare valuation signal that has shown up only once before in the years leading to the dot-com bust. Investors in the S&P 500, Dow Jones Industrial Average, and Nasdaq Composite are still sitting on double-digit year gains, but the price paid for those earnings is now extreme by long-run standards.
For a reader holding broad U.S. index exposure, the message is simple: the market can still rise from here, but the margin for error is thinner when the CAPE ratio is this elevated. The reading does not force a sell decision by itself, yet it does say future returns have to come from a higher starting price.
Shiller CAPE above 40
40 is the number that matters most here. The CAPE ratio measures how much investors are paying today for every dollar of S&P 500 earnings averaged over the last 10 years, and a reading above that line has happened only twice. The first came in the years leading up to the dot-com bust; the second is now.
17 is the rough average across about 150 years of market history, which makes the current reading look stretched even before you compare it with the 24 marker. The ratio crossed 24 on six occasions and has stayed above that level for much of the last decade, but 40 sits in a different category altogether.
Double digits in 2026
Double digits are the backdrop for the rally now. The S&P 500, Dow Jones Industrial Average, and Nasdaq Composite are all up double digits on the year, and if sentiment stays positive they could finish 2026 with a fourth consecutive year of double-digit annual returns. That would not have happened since before the dot-com bubble popped in 2000.
The market is in a bull phase of extreme optimism, and the strength is concentrated in a relatively small group of megacap companies. That combination can carry indexes higher for a while, but it also leaves the broad market leaning on a narrow base while valuations climb.
30 is still expensive
30 is already very expensive territory, and the CAPE ratio has almost no historical precedent above that level because it has happened only once before. Sharp declines tend to follow huge run-ups, which is why the current reading deserves attention even without turning into a forecast for an immediate break.
There is no reason to panic, and the bull market could continue for years. The unresolved question is how long a market can stay above 40 on the CAPE ratio before price and earnings realign, if they do at all.
