S&P 500 Shiller CAPE Ratio Reaches 41, Matching Historic Valuation Peaks
Resolved · market structure · Occurred · Assessed · 1 sources
This assessment is dated 2026-09-06. Check what remains unresolved below before relying on it.
What changed relative to expectations?
A CAPE multiple of 41 compresses the equity risk premium relative to nominal Treasury yields, amplifying multiple contraction risk on macro shocks.
| Question | What the evidence establishes |
|---|---|
| What was reported? | Reported factThe S&P 500 Shiller Cyclically Adjusted Price-to-Earnings (CAPE) ratio has climbed to 41. |
| What else was confirmed? | Reported factCAPE valuations at or above 41 have occurred only twice previously in market history since 1871. |
| Does the valuation support acting? | UnknownRequires applying the change to specific holdings. |
| What would change the assessment? | Unknown10Y Real Yield vs CAPE Yield Gap — Monitor spread between S&P 500 earnings yield and 10-year TIPS yield |
What would this event cost your holdings?
Apply your own hypothetical returns to current holding values. The calculator does not infer security effects from this event.
Test this event against my holdingsReported facts
- · The S&P 500 Shiller Cyclically Adjusted Price-to-Earnings (CAPE) ratio has climbed to 41.
- · CAPE valuations at or above 41 have occurred only twice previously in market history since 1871.
- · Tariff implementation risks, geopolitical upward pressure on crude oil, and Treasury supply are cited as potential multiple headwinds.
Public research record
Research framework · page evidenceCompleted event assessment
equity risk premium compression on elevated cyclically adjusted multiples
| Type | Claim | Scope |
|---|---|---|
| Assumption | The S&P 500 Shiller Cyclically Adjusted Price-to-Earnings (CAPE) ratio has climbed to 41. | 2026-09-06 |
| Interpretation | equity risk premium compression on elevated cyclically adjusted multiples | SPY |
Countercase, invalidators, and sources
Rapid corporate earnings acceleration depresses the cyclically adjusted denominator, normalizing multiples organically.
- · 10Y Real Yield vs CAPE Yield Gap — Monitor spread between S&P 500 earnings yield and 10-year TIPS yield
- The Stock Market Has Done This Only 2 Times Since 1871 · 2026-09-06
What remains unresolved
- Base path
- Equity indices trade in an elevated multiple band with heightened sensitivity to nominal interest rate fluctuations.
- Adverse path
- Tariff or oil price spikes trigger equity multiple de-rating toward historical median levels.
- Supportive path
- Rapid corporate earnings acceleration depresses the cyclically adjusted denominator, normalizing multiples organically.
- · 10Y Real Yield vs CAPE Yield Gap — Monitor spread between S&P 500 earnings yield and 10-year TIPS yieldthis week
Evidence
- The Stock Market Has Done This Only 2 Times Since 18712026-09-06
“The S&P 500 Shiller CAPE ratio has reached 41, its highest level since the dot-com bubble peak, occurring only twice before in 155 years.”
Supports: S&P 500 Shiller CAPE ratio has reached 41, occurring only twice before since 1871.