A cyclical company at the very top of its cycle earns record profits — and on those profits, its P/E looks low, so it screams "cheap" at the exact moment it is most dangerous. The same trap works for a whole market. The ordinary P/E, built on a single year of earnings, is at its most misleading precisely at the extremes where you most need it to be honest. The Shiller PE is the fix.
- Price
- the current index or share price
- Real earnings
- each year’s earnings adjusted for inflation to today’s money
- 10 years
- a window chosen to span a full business cycle
Example: If an index trades at 24,000 and its ten-year average real earnings are 1,000, its CAPE is 24 — to be judged against that index’s own historical CAPE range, not another country’s.
What a high CAPE does and does not tell you
A high CAPE says a market is expensive relative to its long-run earning power, and history shows that buying at high CAPE levels has tended to produce lower returns over the following ten years or so. What it emphatically does not do is time anything: a market can stay expensive, and get more expensive, for years before it matters. CAPE shapes your long-horizon expectations — how much return the next decade is likely to offer — not your decision to buy or sell this month.
At the peak of an earnings boom, a cyclical market shows a low ordinary P/E. Why might its CAPE tell a very different story?
Cyclical company peak profit pe — us profit pe P/E kam dikhta hai, "sasta" lagta hai, theek jab sabse mehnga hai. Poore market pe bhi wahi jaal. Shiller PE (CAPE): price ÷ pichhle 10 saal ki inflation-adjusted average earnings — ek saal ki jagah poora cycle. Toh ek peak ya trough saal dhoka nahi de sakta; market ko normalised, mid-cycle kamai ke against naapta hai. High CAPE = agle das saal kam return (par timing tool nahi — years tak mehnga reh sakta). India ka CAPE apni history se compare karo, US se nahi; aur yeh index ke liye hai, single stock ke liye nahi.
- The Shiller PE (CAPE) divides price by ten years of inflation-adjusted average earnings.
- It smooths the business cycle, so a peak or trough year cannot distort it.
- An ordinary P/E is most misleading at cycle extremes; CAPE fixes that.
- A high CAPE implies lower long-run returns but is a poor timing tool.
- Use it for indices, against their own history — not for single stocks or cross-country.
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Common questions
Short, direct answers to what people ask about this topic.
- what is the shiller pe
- The Shiller PE, also called the CAPE ratio (Cyclically Adjusted Price-to-Earnings), is a valuation measure that divides price by the average of the last ten years of inflation-adjusted earnings, rather than by a single year’s earnings like an ordinary P/E. Developed by economist Robert Shiller, it is used mainly to judge whether a whole market or index is expensive or cheap relative to its own history. Averaging a decade of earnings smooths out the business cycle, so a temporary peak or slump in profits does not distort the picture.
- how is the cape ratio calculated
- You take the current index level and divide it by the average of the past ten years of earnings, with each year’s earnings adjusted for inflation to today’s money. The ten-year window is the key: it deliberately spans a full business cycle so that unusually high or low earnings in any single year are averaged away. The result is a P/E that reflects normalised, mid-cycle earning power rather than whatever the last twelve months happened to produce.
- why use cape instead of a normal pe
- Because a normal P/E can be dangerously misleading at cycle extremes: at the top of a boom, earnings are unusually high, so the P/E looks low and the market looks cheap exactly when it is most expensive — and at the bottom of a bust, depressed earnings make the P/E look high just when the market is cheapest. CAPE fixes this by using ten years of earnings, so it is not fooled by a single peak or trough year. It is built to answer "is this market expensive versus its own long-run normal?"
- is the cape ratio useful for india
- It is a useful long-term gauge of whether Indian indices are richly or cheaply valued versus their own history, and a high CAPE has historically been associated with lower returns over the following decade — but it is a poor timing tool, because a market can stay expensive for years. India’s CAPE also tends to sit higher than developed markets’ because of faster expected growth, so it should be compared to India’s own history rather than to the US. Treat it as context for long-horizon expectations, not a buy or sell signal.