The current Shiller PE (CAPE / P-E10) for the US stock market — the long-term valuation gauge that smooths 10 years of inflation-adjusted earnings. Its historical average is around 16-17.
As of August 2026, the Shiller PE ratio (CAPE) for the US stock market is 42.04, which is extremely elevated — near historic highs. The Shiller PE compares the S&P 500 price to its average inflation-adjusted earnings over the past 10 years; its long-term historical average is around 16 to 17, so today's reading points to an expensive market by historical standards.
Cyclically Adjusted Price-to-Earnings ratio (P/E10) · as of August 2026
Monthly history back to 1871. The dashed line marks the average for the selected period — note the peaks around 1929, the 2000 dot-com bubble, and today.
The standard P/E ratio divides price by a single year of earnings, which swings wildly across the business cycle. The Shiller PE (CAPE) instead uses the average of 10 years of inflation-adjusted earnings, producing a much steadier long-term valuation signal. A high reading means investors are paying a lot for each dollar of smoothed earnings — historically a sign of an expensive, overvalued market and lower expected returns over the following decade. It pairs naturally with the Buffett Indicator, which measures valuation a different way (total market cap to GDP).
The Shiller PE, or CAPE (Cyclically Adjusted Price-to-Earnings ratio, also called P/E10), divides the S&P 500 price by the average of its inflation-adjusted earnings over the past 10 years. Smoothing earnings across a full decade strips out the business cycle, giving a steadier read on whether the market is cheap or expensive than the standard one-year P/E ratio.
Over its roughly 150-year history the Shiller PE has averaged about 16 to 17. Readings in the high teens or below have been historically cheap, the low-to-mid 20s are above average, and readings above 30 are rare and very expensive — territory seen mainly around 1929, the 1999 to 2000 dot-com peak, and the period since 2021.
Not necessarily, and not on any timetable. A high CAPE has historically been associated with lower stock returns over the following decade rather than an imminent crash, and the market can stay expensive for years. It is a long-horizon valuation gauge, best used to calibrate return expectations rather than to time entries and exits.
Yes — it shows the current, latest reading and refreshes automatically. The Shiller PE is a monthly series and the current month moves with the S&P 500, so the live value reflects the most recent available data.