Indexy a trhy
Bull Market and Bear Market: How to Recognize Them
Key takeaways
- A bear market is technically defined as a decline of 20% or more from the peak.
- A bull market has no precise upper boundary — it is a phase of sustained long-term growth.
- Bear markets are painful, but historically they have always ended and been followed by a new bull market.
- Attempting to precisely time exit and re-entry costs most investors meaningful return.
- Regular investing via DCA works even in a bear market — you buy at lower prices.
A bear market occurs when a stock index falls 20% or more from its previous peak; a bull market is a phase of sustained growth without such a drawdown.
Definitions and numbers
The convention is clear: bear market = a decline of 20% from the peak. A correction is a smaller drop — typically 10–20%. The boundaries are analytical, not natural law, but they help communication. The difference between a correction and a crash is covered in the follow-up article.
How long bear markets last
Historical S&P 500 data since 1928 shows that bear markets last on average about 9–10 months. The longest (dot-com, 2007–2009) exceeded two years. By contrast, the average bull market lasts more than 4 years. In other words: investors spend significantly more time in bull markets than in bear markets.
How to behave in a bear market
The most costly decision is to sell in panic and wait for the "right moment" to return. The problem: most investors miss that moment because the strongest rallies arrive unexpectedly.
- Do not change your strategy — a portfolio built for your goals should survive a bear market.
- Keep up your DCA — with regular investing you buy at lower prices, the cost-averaging effect works in your favor.
- Review your allocation — if the decline is causing you sleepless nights, the risk in your portfolio may be too high.
A bear market is not the end of the world
Every bear market in history has been overcome. The patient investor who did not panic has always reached new highs. The power of compounding and a long time horizon is on their side — how this works mathematically is explained in the article on compound interest.
FAQ
What is a bear market?
Technically, a decline of 20% or more in the stock market from its previous peak. It is a convention — the 20% threshold is an analytical tool for communication, not a precise natural law.
How long do bear markets last?
On average 9–10 months, but it can be more than 2 years. The key point is that historically every bear market has ended and a new bull market with new highs has followed.
Should I sell stocks in a bear market?
Generally not — if you have a properly set portfolio and a sufficiently long investment horizon. Panic-selling and waiting for the "right moment" to return costs most investors a significant portion of their long-term return.