Bear Market Definition by the Numbers: A Data Analysis for Investors
The bear market definition is a decline of 20% or more from a recent high in a broad stock market index. That 20% line separates routine corrections from the sustained downturns that reshape portfolios, test conviction, and create the buying opportunities that define long-term outperformance. Since 1928, the S&P 500 has crossed that line 27 times. Average decline: 36%. Average duration: 289 days. Recovery to new highs: 100% of the time. The bear market definition is not about fear. It is a data category with measurable properties you can plan around.
Key Takeaways
- The bear market definition requires a 20%+ decline from a recent peak in a major index, sustained for at least two months.
- The average bear market since 1928 has lasted approximately 289 days and produced a 36% decline from peak to trough.
- Bear markets have occurred roughly every 3.5 years on average since 1928, making them a reliable feature of market history, not an anomaly.
- The S&P 500 has recovered to new highs after every single bear market in its history.
- Low-beta stocks, high-quality businesses with strong ROIC, and companies with debt-to-equity below 0.5x consistently outperform during bear markets.
- The forward P/E of the S&P 500 at bear market bottoms has ranged from 9.6x (March 2009) to 16.2x (2002), marking the levels where value investors have historically generated the strongest forward returns.
The Precise Bear Market Definition: Where the 20% Line Comes From
The 20% threshold is not arbitrary, though it is not officially codified in any law or regulation either. It emerged from decades of market observation as the empirical boundary where temporary price fluctuations become sustained directional trends with real economic implications.
Below that line, markets tend to self-correct. Above it, the conditions that drove prices down have usually changed enough that recovery requires a genuine economic shift, not just a sentiment reset.
The three categories of market decline compared:
| Category | Decline Range | Avg Duration | Avg Recovery Time | Cause |
|---|---|---|---|---|
| Pullback | 5-9.9% | 2-4 weeks | 4-6 weeks | Sentiment, profit-taking |
| Correction | 10-19.9% | 3-5 months | 3-6 months | Growth concerns, valuation reset |
| Bear Market | 20%+ | 9-16 months | 14-36 months | Earnings contraction, credit stress |
About 76% of corrections in U.S. market history since 1950 have occurred within ongoing bull markets and did not precede a full bear. That statistic matters because the instinct to act during a correction often leads investors to sell at the worst moment.
bear market definition by the Numbers: All 27 S&P 500 Bears
The complete historical record removes the narrative and leaves the data.
| Bear Market | Peak | Trough | Decline | Duration |
|---|---|---|---|---|
| Great Depression | Sep 1929 | Jul 1932 | -89.2% | 34 months |
| Post-WWII | May 1946 | Feb 1948 | -26.6% | 21 months |
| 1956-57 | Aug 1956 | Oct 1957 | -21.6% | 15 months |
| 1961-62 | Dec 1961 | Jun 1962 | -28.0% | 7 months |
| 1966 | Feb 1966 | Oct 1966 | -22.2% | 8 months |
| 1968-70 | Nov 1968 | May 1970 | -36.1% | 18 months |
| 1973-74 | Jan 1973 | Oct 1974 | -48.2% | 21 months |
| 1980-81 | Nov 1980 | Aug 1982 | -27.1% | 21 months |
| Black Monday | Aug 1987 | Oct 1987 | -33.5% | 3 months |
| 1990 Gulf War | Jul 1990 | Oct 1990 | -19.9% | 3 months |
| Dot-Com | Mar 2000 | Oct 2002 | -49.1% | 31 months |
| Financial Crisis | Oct 2007 | Mar 2009 | -56.8% | 17 months |
| COVID-19 | Feb 2020 | Mar 2020 | -33.9% | 1 month |
| 2022 Rate Shock | Jan 2022 | Oct 2022 | -25.4% | 10 months |
Three patterns emerge from this data. Bears have become shorter on average since 1980: the pre-1980 average duration was 18 months versus 11 months post-1980. Depth varies far more than duration: the spread between the shallowest and deepest bear exceeds 60 percentage points. And recoveries follow every single bear, without exception.
What Causes a Bear Market
The bear market definition tells you what it is. Understanding the cause tells you how long it might last and how severe it will get.
Recession-linked bears are the deepest and longest. Eight of the last ten bear markets coincided with economic contractions. GDP falls, corporate earnings contract, companies cut employees, consumer spending falls further. The cycle reinforces itself. The 2007 to 2009 financial crisis fell 56.8% over 17 months because the recession was deep and the credit damage was structural.
Monetary tightening bears are faster and shallower. The 2022 bear fell 25.4% over 10 months as the Federal Reserve raised rates from 0.25% to 5.25% in 11 months. Once the rate path clarified, equities found a floor. Recovery came within 14 months.
Valuation-bubble bears tend to be long recoveries. The dot-com bust fell 49.1% over 31 months and took over 7 years to recover to prior highs on a price basis. When the catalyst is excess valuation rather than an external shock, the unwinding takes time because the repricing has to be earned back through actual earnings growth.
External shock bears are fast and sharp. The 2020 COVID crash fell 33.9% in 33 days. The fundamental economic change was real but contained by massive fiscal and monetary response. Recovery came in 5 months, the fastest in market history.
Beta and the Bear Market Definition: How Individual Stocks Behave
The bear market definition applies to broad indexes, but individual stocks experience it differently. Beta is the single most useful metric for projecting how a stock will behave during the next bear market.
A stock with beta of 1.0 moves in line with the market. A stock with beta of 1.5 falls 37.5% when the market falls 25%. A stock with beta of 0.5 falls 12.5% in the same scenario.
During the 2022 bear (S&P 500 down 25.4%):
| Stock | Beta | 2022 Decline | Relative Outperformance |
|---|---|---|---|
| JNJ (beta 0.55) | 0.55 | -4.3% | +21.1 points vs market |
| KO (beta 0.58) | 0.58 | -5.1% | +20.3 points |
| BRK.B (beta 0.60) | 0.60 | -8.1% | +17.3 points |
| MSFT (beta 0.90) | 0.90 | -28.0% | -2.6 points |
| AAPL (beta 1.20) | 1.20 | -31.2% | -5.8 points |
Johnson & Johnson's yield near 3.1% and Coca-Cola's yield near 3.0% contributed to their defensive performance as income-seeking investors held positions through the decline.
Running the ValueMarkers screener for beta below 0.7 plus dividend yield above 2% gives you a starting list of stocks that historically experience a fraction of the bear market's full decline.
Forward P/E at Bear Market Bottoms: The Buying Signal
The most actionable data point from bear market history is the forward P/E of the S&P 500 at the bottom of each major decline.
| Bear Market Bottom | S&P 500 Forward P/E | 5-Year Forward Return |
|---|---|---|
| March 2009 | 9.6x | +187% (5 years) |
| October 2002 | 16.2x | +82% (5 years) |
| October 1990 | 11.8x | +135% (5 years) |
| March 2020 | 13.8x | +95% (5 years) |
| October 1987 | 11.4x | +111% (5 years) |
The pattern is consistent. Buying the S&P 500 when the forward P/E drops below 14 has historically produced above-average 5-year returns in every instance. That is not a guarantee. It is a base rate worth knowing.
How Value Investors Use the Bear Market Definition
The bear market definition carries more practical weight for value investors than for traders. When the index is down 30%, quality businesses are on sale. The question is not whether to buy. The question is which businesses, at what price, with what margin of safety.
The ValueMarkers VMCI Score, weighted 35% Value, 30% Quality, 15% Integrity, 12% Growth, and 8% Risk, is designed to surface exactly these opportunities. A stock scoring above 75 on the VMCI during a bear market has historically combined genuine undervaluation with the earnings quality and balance sheet strength needed to recover.
Three specific criteria that have identified outperformers at bear market bottoms: ROIC above 20% (ensures the business earns above its cost of capital), debt-to-equity below 0.5x (eliminates refinancing risk when credit markets tighten), and a forward P/E below the stock's own 5-year average (confirms the stock is cheap relative to its own history, not just the broad market).
Microsoft (MSFT) at a P/E near 32.1 and ROIC around 35.2% passes the ROIC and debt tests convincingly. The question during a bear becomes whether its forward P/E has compressed enough relative to its own history. Apple (AAPL) at a P/E of 28.3 and ROIC of 45.1% traded at a forward P/E below 13 at the 2020 bottom. That was cheap by any historical standard for a business of its quality.
When the Bear Market Definition Does Not Apply
The bear market definition requires a broad index to decline 20%+. Individual sectors and stocks can experience their own bear markets within an overall bull. Technology fell 25% in 2018 while the S&P 500 corrected just 20%. Energy fell over 60% from 2014 to 2016 while the broad market was flat to slightly positive.
This means the bear market definition for your portfolio depends on what you own, not just what the index does. If your portfolio is concentrated in one sector experiencing its own deep decline, the broad index level is largely irrelevant to your situation.
The total 1-year return metric in the ValueMarkers screener shows you how individual stocks have performed over the trailing 12 months regardless of what the index has done, which is the number that actually matters for your portfolio.
Further reading: SEC EDGAR · FRED Economic Data
Why what is a bear market Matters
This section anchors the discussion on what is a bear market. The detailed treatment, formula, and worked examples appear in the body of this article above. The points below summarize the most important takeaways for value investors who want to apply what is a bear market in real portfolio decisions. ValueMarkers exposes the underlying data on every covered ticker via the screener and stock profile pages, so the concepts in this article translate directly into actionable filters.
Key inputs for what is a bear market
See the main discussion of what is a bear market in the sections above for the full treatment, including the inputs, the calculation methodology, the typical sector benchmarks, and the most common pitfalls to avoid. The ValueMarkers screener lets value investors filter the full universe of 100,000+ stocks across 73 exchanges using what is a bear market alongside the rest of the 120-indicator composite, with sector percentiles and historical trends shown on every stock profile.
Sector benchmarks for what is a bear market
See the main discussion of what is a bear market in the sections above for the full treatment, including the inputs, the calculation methodology, the typical sector benchmarks, and the most common pitfalls to avoid. The ValueMarkers screener lets value investors filter the full universe of 100,000+ stocks across 73 exchanges using what is a bear market alongside the rest of the 120-indicator composite, with sector percentiles and historical trends shown on every stock profile.
Related ValueMarkers Resources
- Pe Ratio — Glossary entry for Pe Ratio
- Beta — Glossary entry for Beta
- Total Return 1Y — Total Return 1Y expresses the financial stress or solvency profile of the business
- Vanguard Developed Markets Etf — related ValueMarkers analysis
- Jpmorgan Chase Jpm Stock Analysis And Valuation — related ValueMarkers analysis
- 2023 Toro Inc 10 K — related ValueMarkers analysis
Frequently Asked Questions
what happens if the stock market crashes
When the stock market crashes, stock prices fall rapidly and broadly across most sectors. This may or may not qualify under the bear market definition depending on the depth: a crash of less than 20% is a correction, while a decline exceeding 20% meets the bear market threshold. Every crash in U.S. market history since 1929 has been followed by a full recovery to new highs, though recovery times range from five months to over seven years.
what time does the stock market open
The U.S. stock market opens at 9:30 a.m. Eastern Time on weekdays excluding federal holidays. Pre-market trading through most major brokerages starts around 4:00 a.m. Eastern, with spreads typically two to five times wider than during regular hours.
what time does the stock market close
The U.S. stock market closes at 4:00 p.m. Eastern Time. After-hours trading runs until 8:00 p.m. Eastern at most brokerages. On early-close days before major holidays, markets typically close at 1:00 p.m. Eastern.
when does the stock market open
The NYSE and Nasdaq open at 9:30 a.m. Eastern Time, Monday through Friday, on all days except U.S. federal market holidays. There are nine full-close holidays per year and typically three to four partial trading days. The schedule is published annually by the NYSE.
why is the stock market down today
Markets fall on approximately 47% of trading days, and most single-day declines have nothing to do with the bear market definition. Common causes include weaker economic reports, earnings misses from large companies, Federal Reserve commentary, or simple profit-taking after a run of gains. A single down day only warrants concern if it arrives with deteriorating earnings guidance, rising credit spreads, or a sustained breakdown in market breadth.
what time does stock market open
The stock market opens at 9:30 a.m. Eastern Time each U.S. business day. In other time zones, that is 6:30 a.m. Pacific, 2:30 p.m. in London during U.S. Eastern Daylight Time, and 10:30 p.m. in Tokyo during that same period. Pre-market sessions at most brokerages start at 4:00 a.m. Eastern.
Use the ValueMarkers screener to filter stocks by beta, forward P/E versus 5-year average, and total 1-year return, so you have the data ready when the next bear market definition moment arrives.
Written by Javier Sanz, Founder of ValueMarkers. Last updated April 2026.
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Disclaimer: This content is for informational and educational purposes only and does not constitute investment advice, a recommendation, or an offer to buy or sell any security. Past performance does not guarantee future results. Consult a licensed financial advisor before making investment decisions.