Bear Market
An extended period of falling prices and generally negative sentiment.
Also called: bearish · bear
Written by Javier Sánchez Ros
In plain language
A bear market is conventionally a decline of 20% or more from a major high, sustained over time rather than a single sharp drop.
Bear markets behave differently from bull markets, not just in direction. Volatility is higher, correlations rise, and rallies are sharp enough to look like reversals repeatedly.
Liquidity thins as declines accelerate, which widens spreads and increases slippage exactly when stops are most likely to trigger.
Worked through
The same share count, twice the real risk
- Calm market: average daily range
- ~1.1%
- Bear market: average daily range
- ~2.6%
- Position
- unchanged
- Daily swing in currency
- more than doubled
Nothing about the position changed. The instrument did: the same number of shares now moves more than twice as much in a day, which means the account is taking on far more variance than the sizing routine believed it was.
Bear markets raise every input at once. Volatility rises, correlations rise so unrelated positions stop diversifying, gaps become larger and more frequent, and liquidity thins out so stops slip further. A position sized by a rule calibrated in calm conditions is quietly running hot on all five.
The adjustment is not to stop trading. It is to let the stop distance widen with the volatility, which automatically shrinks the position — and if the sizing rule is being followed properly, that happens on its own rather than requiring a decision.
Rallies are the other trap. Bear markets produce the sharpest upward moves in the record, which look like the turn and are usually not, and which punish shorts sized for calm conditions just as hard.
Why it matters
The same position size carries more real risk in a bear market because volatility and gap risk are both elevated. Sizing should adjust with the regime.
Common mistakes
- Repeatedly buying dips on the assumption the previous regime still applies.
- Keeping bull-market position sizes while volatility has doubled.
- Underestimating how convincing counter-trend rallies can be.
Keep exploring
These concepts are connected. Understanding one usually makes the next one easier.
An extended period of rising prices and generally positive sentiment.
How much and how quickly an asset’s price moves over a given period.
The decline from an account’s peak value to its lowest point before a new peak.
The hidden risk of holding several positions that tend to move together.
How easily an asset can be bought or sold without moving its price.