S&P 500 Shiller CAPE Ratio Reaches 41 Matching Rare Historical Valuation Extremes
Resolved · macro data · 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 Shiller CAPE multiple of 41 compresses the equity risk premium over 10Y Treasuries, amplifying downside sensitivity to rate volatility and margin contraction across SPY.
| Question | What the evidence establishes |
|---|---|
| What was reported? | Reported factThe S&P 500 cyclically adjusted price-to-earnings (CAPE) ratio has reached 41. |
| What else was confirmed? | Reported factA Shiller CAPE multiple of 41 has occurred only twice before in market history since 1871, including the dot-com bubble peak. |
| Does the valuation support acting? | UnknownRequires applying the change to specific holdings. |
| What would change the assessment? | Unknown10Y Real Yield vs CAPE Ratio — Monitor whether 10Y real yields rise above 2.10%, increasing de-rating pressure on 40x+ CAPE multiples. |
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 cyclically adjusted price-to-earnings (CAPE) ratio has reached 41.
- · A Shiller CAPE multiple of 41 has occurred only twice before in market history since 1871, including the dot-com bubble peak.
- · Macro crosscurrents including tariff proposals and energy price pressures intersect with elevated multiple levels.
Public research record
Research framework · page evidenceCompleted event assessment
equity multiple compression under high valuation percentiles
| Type | Claim | Scope |
|---|---|---|
| Assumption | The S&P 500 cyclically adjusted price-to-earnings (CAPE) ratio has reached 41. | 2026-09-06 |
| Interpretation | equity multiple compression under high valuation percentiles | SPY |
Countercase, invalidators, and sources
Earnings growth reaccelerates past 20% annualized, naturally reducing the cyclically adjusted multiple without index drawdowns.
- · 10Y Real Yield vs CAPE Ratio — Monitor whether 10Y real yields rise above 2.10%, increasing de-rating pressure on 40x+ CAPE multiples.
- The Stock Market Has Done This Only 2 Times Since 1871 · 2026-09-06
What remains unresolved
- Base path
- Equity indices experience choppy sideways trading as high multiples absorb gradual monetary policy adjustments.
- Adverse path
- Persistent inflation combined with trade tariffs triggers a sharp multiple de-rating toward historical mean levels.
- Supportive path
- Earnings growth reaccelerates past 20% annualized, naturally reducing the cyclically adjusted multiple without index drawdowns.
- · 10Y Real Yield vs CAPE Ratio — Monitor whether 10Y real yields rise above 2.10%, increasing de-rating pressure on 40x+ CAPE multiples.this 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 prior in market history.