Disclaimer: This article is for educational purposes only and does not constitute financial or investment advice. Past market performance does not guarantee future results. All investments carry risk, including the risk of total loss. Please consult a licensed financial advisor before making investment decisions.
I became interested in markets during the 2020 crash — the kind of crash that happens so fast it’s disorienting. In three weeks, the S&P 500 fell 34%. I had no financial background and desperately needed to understand what was happening. This is the article I wish I’d had: what bear markets actually are, how they’ve behaved historically, and what the data says about getting through them.
The Definition
A bear market is conventionally defined as a decline of 20% or more from a recent peak in a broad market index, typically the S&P 500. The 20% threshold is arbitrary — it was established by market convention, not mathematical principle — but it’s universally used and has become self-reinforcing. A 19% decline produces different institutional behavior than a 20% decline because the label changes.
A correction (10-20% decline) is distinct from a bear market — corrections are more frequent and typically shallower. Bear markets signal more significant structural shifts in economic expectations.
Historical Bear Markets: The Data
Based on S&P 500 data compiled by Ben Carlson of Ritholtz Wealth Management and cross-referenced with data from Ned Davis Research, since 1928 there have been approximately 26 bear markets in the U.S. stock market (using the formal 20% definition). Key statistics:
- Average decline: approximately 36%
- Average duration: approximately 9.6 months from peak to trough
- Median duration: approximately 8 months (the distribution is right-skewed by long bear markets)
- Longest bear market: the Great Depression era (1929-1932), approximately 34 months, 83% decline
- Shortest bear market: COVID crash (2020), approximately 1 month, 34% decline
Secular vs. Cyclical Bear Markets
Not all bear markets are equivalent. Cyclical bear markets occur within a broader long-term uptrend — they’re painful but relatively brief (months to a year or two). Secular bear markets are long-term periods where stocks trend flat or downward over many years, punctuated by cyclical bull runs that don’t reach new sustained highs. The 1966-1982 period in the U.S. is the most-cited example of a secular bear market — 16 years of essentially flat inflation-adjusted returns.
The distinction matters for planning purposes. A cyclical bear market rewards patience. A secular bear market may require tactical adjustments to portfolio strategy.
How Long Do Recoveries Take?
The recovery side is as important as the decline. Historical data shows:
- The average bear market recovery period (trough to new all-time high) is approximately 2 years
- Most bear markets (outside of secular bear markets) are followed by bull markets that recoup losses within 3-5 years
- The dot-com bear market (2000-2002) took approximately 7 years to fully recover
- The 2008-2009 financial crisis took approximately 5-6 years to recover to prior highs
What the Research Says About Investor Behavior
DALBAR’s annual Quantitative Analysis of Investor Behavior consistently shows that average investor returns lag index returns by 1-2% annually — primarily due to buying near peaks and selling near troughs. Research by Brad Barber and Terrance Odean at UC Berkeley, published in Journal of Finance (2000), found that frequent traders significantly underperformed buy-and-hold investors, with the gap widening during volatile periods. Bear markets are when behavioral errors are most expensive.
What History Suggests (Not Advice)
Historically, every U.S. bear market has eventually ended. Diversified long-term investors who did not sell at the bottom of any major bear market (including the Great Depression) eventually recovered. This historical pattern is real — though past patterns do not guarantee future results, and individual circumstances vary enormously. These are historical facts, not predictions.
The Most Useful Thing to Know
Bear markets feel permanent when you’re in them. The psychological experience of watching a portfolio decline for months — particularly the second and third time it appears to bottom and then declines further — is genuinely difficult. Having pre-decided, written rules about what you will and won’t do during drawdowns (“I will not sell more than X% of holdings during a decline greater than 20%”) is more effective than trying to reason through those decisions in real time.