Investing at All-Time Highs: What the Data Actually Shows

The Fear That Keeps Investors on the Sidelines

Every time a major stock index hits a new all-time high, the same pattern plays out. Headlines warn of overheated markets. Investors pause contributions. Some pull money out entirely, convinced that what goes up must come down. It feels rational. It feels prudent. And according to decades of market data, it is almost certainly costing those investors money.

Investing at all-time highs is one of the most emotionally charged decisions in personal finance — and one of the most misunderstood. The anxiety is understandable. But the data tells a story that runs directly counter to the instinct to wait for a pullback before putting capital to work.

This article unpacks what market all-time highs actually mean, what historical return data says about investing at those moments, and why stock valuations — not index levels — are the metric that deserves serious attention.

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What an All-Time High Actually Means (And Why It's Often Misleading)

When the S&P 500 or the TSX Composite hits a new peak, the figure being reported is almost always a price-only index level — meaning it tracks share prices but excludes dividends. This is a significant omission.

Dividends represent a meaningful portion of total stock market returns over time. When a company pays a dividend, the share price drops by roughly the dividend amount on the ex-dividend date. From a price-index perspective, this looks like a loss. Economically, it isn't — the investor received cash. The result is that price-only indices systematically undercount both the frequency and magnitude of all-time highs.

According to academic research cited by PWL Capital's Chief Investment Officer Ben Felix, newspaper coverage of stock market performance tends to be more negative during periods of higher dividend yields — precisely because dividends mechanically suppress reported index levels. Investors are, in effect, being made to feel worse about a return profile that is actually better than it looks on screen.

There are two additional distortions worth noting:

• Inflation: Index levels are nominal. Even with zero real returns, an index should rise over time simply because prices across the economy are rising. A new all-time high in nominal terms can coincide with flat or negative real returns.
• Positive expected returns: Stocks have historically delivered positive long-term returns. Indices hitting new highs over time is not a warning signal — it is the expected outcome of owning productive businesses. It should be boring news. The fact that it isn't is a media phenomenon, not a financial one.

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The Data on Returns After All-Time Highs

Using total return indices — which include reinvested dividends and are a far more accurate representation of investor experience — the data from 10 developed markets spanning 1970 through mid-2026 is instructive.

Key findings:

• On average across 10 countries, 20% of months recorded an all-time high in the total return index.
• The US market hit all-time highs in 30% of months; Canada in 23%.
• The global world index hit all-time highs in 31% of months, partly because international diversification smooths out country-level volatility.
• Italy, whose stock market has underperformed structurally, recorded the lowest frequency at just 9%.

All-time highs are not rare. They cluster together — a feature consistent with the well-documented momentum effect in equity markets, where periods of strong returns tend to be followed by further gains in the near term before mean reversion reasserts itself over longer horizons.

On the question of returns after all-time highs:

• In the US market, 1-year, 3-year, and 5-year returns following all-time highs have historically been higher than returns following all other months.
• At the 10-year horizon, returns are slightly lower after all-time highs — a pattern likely explained by elevated valuations at market peaks, not by the fact of the peak itself.
• The World Index shows similar patterns, with particularly strong 1-year returns following all-time highs, again consistent with momentum.

The takeaway is direct: historically, investors who deployed capital at all-time highs did not systematically underperform those who waited. In many cases, they outperformed in the short run.

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The Gambler's Fallacy Is Quietly Expensive

The psychological mechanism driving all-time high anxiety has a name: the gambler's fallacy. It is the mistaken belief that a string of positive outcomes makes a negative outcome more likely — that the market is somehow "due" for a correction after an extended run-up.

This logic applies cleanly to roulette. It does not apply cleanly to equity markets, for a simple reason: stock returns are not generated by a fixed-probability mechanism. They reflect the aggregate judgment of millions of market participants pricing in future corporate earnings, interest rates, geopolitical risk, and countless other variables simultaneously.

While stock returns are not perfectly random — momentum and valuation effects do exist — the gambler's fallacy is not a useful guide. The fact that markets have risen for 18 months tells you very little about what they will do in month 19. The data bears this out. Investors who sit on cash waiting for a pullback face a compounding problem: the opportunity cost of being out of the market accumulates daily, and there is no reliable signal that tells them when to get back in.

This is the core problem with market timing. To succeed, an investor must be right twice: once when exiting (correctly anticipating a decline) and again when re-entering (correctly identifying the bottom). Professional fund managers with full-time research teams fail at this consistently. Individual investors face even longer odds.

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Valuations Are a Different — and More Important — Conversation

Index levels and market valuations are distinct concepts that often get conflated. The distinction matters enormously for setting realistic return expectations.

The Shiller Cyclically Adjusted Price-Earnings ratio (CAPE) is the most widely respected measure of stock market valuation. It compares current stock prices to average inflation-adjusted earnings over the prior 10 years, smoothing out business cycle noise. The logic is straightforward: when you buy a stock, you are buying a claim on future earnings. The higher the price you pay relative to those earnings, the lower your expected return — all else equal.

Analysis of 10 developed markets from 1982 through end-2024 confirms the relationship:

• Higher starting CAPE ratios are associated with lower realized 10-year returns on average.
• The relationship is real but noisy — high-valuation starting points have sometimes preceded strong returns, and low-valuation starting points have sometimes preceded disappointing ones.
• This noise makes valuation-based market timing genuinely difficult to execute in practice, even for sophisticated investors with the right framework.

At the time of this writing, the US market's CAPE ratio is approaching levels last seen before the dot-com bust — a fact worth acknowledging with clear eyes. However, two important caveats apply:

1. The US is not the whole world. Including international developed and emerging markets in a portfolio exposes investors to a much wider range of starting valuations, many of which are significantly less stretched than US equities. A globally diversified investor is not fully exposed to US valuation risk.
2. High valuations compress expected returns; they do not guarantee losses. The distribution of outcomes at any given CAPE level is wide enough that timing the market based on valuation alone has historically been an unreliable strategy.

The prudent response to elevated valuations is not to exit equities. It is to calibrate return expectations downward and ensure your financial plan accounts for a range of scenarios — including a prolonged period of below-average returns.

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What the Evidence Actually Recommends

Combining the research on all-time highs and market valuations produces a set of conclusions that are unglamorous but well-supported:

• Stay invested. Historically, the expected return following an all-time high is positive at every time horizon examined. The cost of sitting on the sidelines — in foregone returns and the near-impossibility of timing re-entry — outweighs the theoretical benefit of avoiding a drawdown.
• Use total return indices, not price-only indices, to evaluate performance. The commonly reported figures systematically understate the market's true performance and make all-time highs look rarer and more alarming than they are.
• Take valuations seriously as a planning input, not a timing signal. If the CAPE ratio suggests lower expected returns over the next decade, factor that into your savings rate, retirement projections, and asset allocation — but don't use it to justify sitting in cash.
• Diversify globally. A portfolio concentrated in US large-cap equities carries both the upside and the valuation risk of a single market. International exposure provides access to more attractively priced markets without abandoning equity returns.
• Remember the two-decision problem. Exiting the market requires two correct decisions: getting out and getting back in. The compounding cost of being wrong on either is substantial.

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The Bottom Line

Investing at all-time highs feels uncomfortable by design. Human psychology is wired to interpret a recent run of good news as a warning, not a green light. But the data, spanning more than five decades and 10 developed markets, does not support the instinct to wait.

All-time highs are normal. They are expected. They occur in roughly 20-30% of months in major markets when measured correctly using total return indices. And the returns that follow them are, on average, positive — and in the short term, often better than the returns following non-peak months.

The more important question is not whether the index is at a high, but whether the market is expensive relative to earnings — and what that implies for your long-term return expectations. Right now, US equity valuations warrant attention and tempered expectations. They do not warrant panic or paralysis.

For investors with a long time horizon and a clear financial plan, the strategy that has worked across markets and decades remains the same: stay in your seat, stay diversified, and let compounding do its work.

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This article is for informational purposes only and does not constitute financial advice. Always consult a qualified financial professional before making investment decisions.

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Frequently Asked Questions

Is it a bad idea to invest when the stock market is at an all-time high?

Historical data across 10 developed markets from 1970 onward suggests it is not. Using total return indices, average returns following all-time highs have been positive at every time horizon studied — and at the 1, 3, and 5-year horizons in the US market, they have actually been higher than returns following non-peak months. The anxiety around all-time highs is largely a psychological response, not a data-driven one.

What is the difference between a price-only index and a total return index?

A price-only index tracks changes in stock prices alone. A total return index also includes the reinvestment of dividends. Because dividends represent a significant portion of long-term equity returns, total return indices are a more accurate measure of what investors actually experience. Notably, using total return indices reveals that all-time highs occur more frequently than price-only reporting suggests, since dividends suppress price-index levels without reflecting an economic loss to the investor.

What is the CAPE ratio and why does it matter?

The CAPE ratio — or Cyclically Adjusted Price-Earnings ratio, developed by economist Robert Shiller — measures stock market valuation by comparing current prices to average inflation-adjusted earnings over the prior 10 years. Higher CAPE ratios have historically been associated with lower realized returns over the following decade. It is a useful tool for setting return expectations, but the relationship is noisy enough that using it as a precise market timing signal has not proven reliable in practice.

Should I try to time the market based on valuations or all-time highs?

The evidence suggests caution here. Market timing requires two correct decisions: when to exit and when to re-enter. Research consistently shows that missing just a handful of the market's best days — which often occur during volatile periods — significantly reduces long-term returns. High valuations are worth incorporating into your financial planning as a basis for more conservative return assumptions, but they are not a reliable trigger for moving to cash. Staying invested in a diversified portfolio aligned with your risk tolerance and time horizon has outperformed reactive timing strategies across most historical periods.