The S&P 500 Shiller CAPE reading hit roughly 36x in April 2026 — a level last seen only twice in the index's entire history. If you own Apple (AAPL), Microsoft (MSFT), or anything else in the Magnificent 7, this single number is the one long-term bears keep waving at you.
The CAPE ratio — Professor Robert Shiller's cyclically-adjusted P/E — is the most-cited long-term valuation signal in finance, and also the most abused. Knowing how to read it (and when to ignore it) is a skill every serious investor builds.
What is the CAPE ratio?
It is a P/E ratio engineered for cycle comparison. Instead of dividing price by trailing earnings, CAPE divides price by the ten-year average of real (inflation-adjusted) earnings. That smooths out the peaks and valleys of the business cycle so you are comparing apples to apples across decades.
Yale's Robert Shiller popularized it in his 2000 book Irrational Exuberance, using data that stretches back to about 1871. The full history is public at multpl.com if you want to play with the numbers yourself — Shiller updates it monthly.
CAPE is also called the Shiller PE, P/E 10, or just "the Shiller ratio." They all mean the same thing.
Why does the 10-year smoothing matter?
Because trailing P/E is unreliable near inflection points. In 2009, S&P 500 earnings were obliterated by the financial crisis. Trailing P/E spiked to absurd levels and some strategists called the market "expensive" — right at the bottom.
CAPE did not spike. By averaging a decade of earnings, it absorbed the 2008-2009 collapse as a small adjustment to an otherwise-normal baseline. At the March 2009 low, CAPE was approximately 13x — historically cheap.
That is the feature, not the bug. Long-term averages of earnings tell you what the business can actually produce across a cycle. A one-year snapshot tells you what last quarter looked like.
What is the current CAPE reading saying?
The S&P 500 Shiller CAPE sat around 36x as of early April 2026, per Shiller's own dataset. Readings above 30x have historically been rare. The four observations above 35x in the series are: 1999–2000 (dot-com), 2021 (post-COVID stimulus peak), early 2025, and now.
This is the "rich" zone, not the "cheap" zone. Readings at this level have historically been followed by lower-than-average forward 10-year real returns.
Here is the rough historical map — use it as a guide, not a prediction:
| CAPE Range |
Historical Frequency |
Rough Subsequent 10-Yr Real Return |
| Below 10x |
Rare (<5% of months) |
~10-12% annualized |
| 10-15x |
Common |
~7-9% annualized |
| 15-20x |
Most common ("normal") |
~5-7% annualized |
| 20-25x |
Elevated |
~3-5% annualized |
| 25-30x |
Expensive |
~1-3% annualized |
| Above 30x |
Rare |
Roughly flat to slightly negative |
Numbers are approximate and based on CAPE-subsequent-returns regression work that Shiller and others have published. Actual outcomes vary widely — the R-squared at any single reading is modest.
Does a high CAPE mean the market will crash?
No. Not in any useful short-term sense. CAPE's predictive power kicks in over 10-to-20 year horizons, not 10-to-20 month ones. Markets can stay "expensive" for many years before mean-reverting.
A reading near 36x tells you two things with reasonable confidence: (1) forward 10-year total returns from S&P 500 index exposure are likely to be meaningfully below the long-term average of about 10% nominal, and (2) drawdown risk is elevated because multiples have more room to compress than expand.
What CAPE does not tell you: timing, sector dispersion, or what to do with individual stocks. Owning AAPL or MSFT at 30x forward earnings in 2015 worked out fine despite a "rich" aggregate CAPE.
How does the Magnificent 7 distort the CAPE reading?
Meaningfully. The top ~10 names — AAPL, MSFT, NVDA, Alphabet (GOOGL), Amazon (AMZN), Meta (META), and a couple of others — now account for roughly one-third of the S&P 500's market cap. These companies carry average CAPE multiples well above the index median.
Strip out the mega-caps and the equal-weighted S&P 500 CAPE is roughly 10 points lower. That is the nuance most "CAPE is flashing red" headlines miss. The pain, if it comes, will be concentrated where the price is — not evenly spread.
That also means mid-caps, small-caps, and international equities (which trade at meaningfully lower CAPE multiples, particularly Hong Kong, China, and parts of Europe) could structurally outperform if the premium at the top reverses. This is the contrarian CAPE playbook — and why asset allocators are increasingly rotating into investment strategies like international value tilts.
What do legendary investors actually do when CAPE is high?
They do not sell everything. They get pickier, and they shift the mix.
Warren Buffett's Berkshire (BRK.B) has historically built cash when aggregate multiples expand — not because CAPE told him to, but because bottom-up value opportunities become scarce. Jeremy Grantham at GMO publishes CAPE-adjusted 7-year asset-class forecasts that have been consistently pointing toward international and small-cap tilts.
The retail lesson, compressed: do not try to time CAPE. Use it as a governor on position sizing and as a prompt to diversify beyond the S&P 500. See how we think about screening across the valuation lens in super investors.
Counter-argument: is CAPE broken in 2026?
Several serious researchers argue yes — or at least that the effective "normal" CAPE has reset permanently higher. Three reasons are cited.
First, accounting has changed. R&D and software investment is increasingly expensed rather than capitalized, which depresses reported earnings versus the 1871–1990 baseline. That alone accounts for a few points of CAPE drift upward.
Second, tax rates are lower. The US corporate tax rate is structurally below its 20th-century average, which means every dollar of pre-tax profit translates to more net income than it used to. A higher CAPE is mathematically consistent with that.
Third, tech margins are higher. A ~20% net margin composition-weighted into the index is a different business than the ~6% margin of the mid-20th century industrial economy.
The counter-counter: you cannot use "this time is different" to excuse a 36x CAPE indefinitely. The four instances of CAPE above 35x in history all ended with multiples compressing — the only question was whether it happened through rolling sideways (1990s pattern) or a hard drawdown (2000, 2008). Trust the framework, respect the nuance.
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