The US stock market is doing something witnessed only 3 times in 154 years — and history makes clear what happens next

If things seem too good to be true on Wall Street, they just might be.

| More on:
A man in a business suit peers through binoculars as two businesswomen stand beside him looking straight ahead at the camera.

Images source: Getty Images

You’re reading a free article with opinions that may differ from The Motley Fool’s Premium Investing Services. Become a Motley Fool member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn More

This article was originally published on Fool.com. All figures quoted in US dollars unless otherwise stated.

For more than two years, the stock market has been virtually unstoppable. Last year, the iconic Dow Jones Industrial Average (DJX: .DJI), broad-based S&P 500 (SP: .INX), and innovation-inspired Nasdaq Composite (NASDAQ: .IXIC) galloped higher by 13%, 23%, and 29%, respectively, with all three indexes notching multiple record-closing highs.

Investors haven't needed to dig too deeply to locate the catalysts fueling this extended rally in equities. In no particular order, the powder keg of the current bull market includes:

  • The rise of artificial intelligence (AI).
  • Better-than-expected corporate earnings.
  • A pullback in the prevailing rate of inflation from a four-decade high.
  • A resilient U.S. economy.
  • The return of Donald Trump to the White House.
  • Investor euphoria surrounding stock splits.

While nothing has slowed this bull market rally, history has often shown that when things seem too good to be true, they usually are.

The stock market has reached this point on three occasions since January 1871

At any given time, there is bound to be a data point, metric, or forecasting tool that spells potential trouble for the U.S. economy and/or Wall Street. Some of the more recent examples include the first notable year-over-year decline in U.S. M2 money supply since the Great Depression, as well as the longest yield-curve inversion on record.

But among the "what if"s for the stock market, none screams louder than a valuation tool that's making history for only the third time in 154 years.

As the old idiom states, "value is in the eye of the beholder." Value is a relatively subjective term, and what one investor considers to be pricey might be viewed as a bargain by another.

The traditional valuation tool on Wall Street is the price-to-earnings (P/E) ratio, which divides a company's share price into its trailing-12-month earnings. While the P/E ratio is a quick value-comparison tool for mature businesses, it doesn't work particularly well with growth stocks and can get easily skewed during turbulent events, such as the COVID-19 pandemic.

A considerably more comprehensive valuation tool that allows for apples-to-apples comparisons is the S&P 500's Shiller P/E Ratio, which is also referred to as the cyclically adjusted P/E Ratio, or CAPE Ratio. The Shiller P/E is based on average inflation-adjusted earnings from the previous 10 years, which means that shock events won't be able to skew its readings.

S&P 500 Shiller CAPE Ratio Chart

S&P 500 Shiller CAPE Ratio data by YCharts.

When the closing bell rang on February 5, the S&P 500's Shiller P/E crossed the finish line with a reading of 38.23. For context, the average reading for the Shiller P/E when back-tested to January 1871 is just 17.2.

What's even more noteworthy is just how rare the magnitude of this deviation is above the historic average. Spanning 154 years, this marks only the third time during a continuous bull market that the S&P 500's Shiller P/E has reached a reading of at least 38.

The other two incidences include an all-time high in December 1999 of 44.19 and first week of January 2022 peak of just over 40. The former occurred just prior to the bursting of the dot-com bubble, which saw the S&P 500 and Nasdaq Composite respectively lose 49% and 78% of their value on a peak-to-trough basis. Meanwhile, the latter gave way to a bear market for the Dow Jones, S&P 500, and Nasdaq Composite between January 2022 and October 2022.

Widening the lens a bit further finds only six instances, including the present, where the Shiller P/E Ratio has surpassed 30 during a bull market in 154 years. All five previous occurrences were followed by declines ranging from 20% to 89% in at least one of the three major stock indexes.

Admittedly, the Shiller P/E isn't a timing tool and provides no clues as to when equities hit a temporary top. But when back-tested 154 years, it does have a flawless track record of foreshadowing eventual (and significant) downside in the stock market.

Time in the market trumps timing the market

While history rhyming and sending the stock market notably lower may not be what investors want to hear, there's a critical difference when it comes to trying to time short-term market moves and putting your money to work over long periods on Wall Street.

The blunt truth is that no matter how much we wish against stock market corrections, bear markets, crashes, and economic downturns, they're a normal and inevitable part of the respective investing and economic cycle. But what's vital to recognise is that cycles for the U.S. economy and stock market aren't mirror images of each other.

For example, the U.S. economy has worked its way through 12 recessions since World War II came to a close in September 1945. Spanning nearly eight decades, nine out of 12 recessions were resolved in less than a year. According to a report from the Congressional Research Service (CRS), the average recession from 1945 through 2009 endured just 11 months.

On the other hand, CRS notes the typical economic expansion stuck around for 58 months between 1945 and 2009, or nearly five years. Prior to the COVID-19 recession taking shape, the U.S. economy was enjoying an expansion that was over 10 years old. In other words, even though economic downturns are inevitable, they're historically short-lived.

This same cyclical nonlinearity can be seen on Wall Street.

The data set above was posted in June 2023 by the researchers at Bespoke Investment Group shortly after the benchmark S&P 500 was confirmed to be in a new bull market. It examines the length of every bull and bear market for this widely followed index dating back to the start of the Great Depression in September 1929.

In the 94-year period examined, the average S&P 500 bear market took 286 calendar days to complete, or about 9.5 months. What's more, the lengthiest bear market on record endured for 630 calendar days in the mid-1970s.

On the other hand, Bespoke's data set found the average of 27 S&P 500 bull markets lasted 1,011 calendar days, or roughly 3.5 times longer than the typical bear market. Further, if you include the current bull market rally (extrapolated to present day), over half — 14 out of 27 — of all bull markets have stuck around longer than the lengthiest bear market.

Short-term moves lower on Wall Street are virtually impossible to forecast. But history has conclusively shown that time in the market is far more valuable than trying to time the market.

This article was originally published on Fool.com. All figures quoted in US dollars unless otherwise stated.

Should you invest $1,000 in Apple right now?

Before you buy Apple shares, consider this:

Motley Fool investing expert Scott Phillips just revealed what he believes are the 5 best stocks for investors to buy right now... and Apple wasn't one of them.

The online investing service he’s run for over a decade, Motley Fool Share Advisor, has provided thousands of paying members with stock picks that have doubled, tripled or even more.*

And right now, Scott thinks there are 5 stocks that may be better buys...

See The 5 Stocks *Returns as of 6 March 2025

Sean Williams has no position in any of the stocks mentioned. The Motley Fool Australia's parent company Motley Fool Holdings Inc. has no position in any of the stocks mentioned. The Motley Fool Australia has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy. This article contains general investment advice only (under AFSL 400691). Authorised by Scott Phillips.

More on International Stock News

Unsure man analysing data on laptop.
International Stock News

Stock market sell-off: Here's why history says investors shouldn't hit the panic button

The U.S. stock market has had a rough start to 2025, with all three major indexes down through March 17.

Read more »

Electric vehicle being charged.
International Stock News

Tesla stock is down by 50%. Time to buy?

Tesla stock is not for the faint-hearted.

Read more »

Woman sitting at a desk shrugs.
International Stock News

Where will Nvidia stock be in 1 year?

Nvidia stock has been sliding throughout 2025.

Read more »

A woman sits in a cafe wearing a polka dotted shirt and holding a latte in one hand while reading something on a laptop that is sitting on the table in front of her
International Stock News

Is Alphabet stock going to $210? One wall street analyst thinks so.

One of the benefits of owning Alphabet stock is that management has various levers it can pull to produce more…

Read more »

Hand with AI in capital letters and AI-related digital icons.
International Stock News

Where will Nvidia be in 1 year?

Predicting where any company will be in 12 months is more of a thought experiment than an exact science.

Read more »

AI written in blue on a digital chip.
International Stock News

2 crashing AI stocks that aren't worth buying on the dip

Let's discuss some reasons why these stocks aren't worth buying on the dip.

Read more »

Modern accountant woman in a light business suit in modern green office with documents and laptop.
International Stock News

Alphabet stock has lost over $500 billion in market cap. Is the Google parent a top AI stock to buy now?

Alphabet is now the cheapest stock in the Magnificent Seven cohort.

Read more »

A woman sits at her computer with her hand to her mouth and a contemplative smile on her face as she reads about the performance of Allkem shares on her computer
International Stock News

Nvidia's top AI event is here: Will Nvidia stock rise during March 18 through March 21?

Nvidia stock got a boost from last year's GTC event, and investors are hoping for the same this year.

Read more »