Every trading account, no matter how good the strategy behind it, spends time below its all-time high. The distance between that high-water mark and the low the account falls to before recovering is called drawdown, and it is one of the most important numbers in trading — arguably more important than the profit figure, because it measures the pain and the risk of a strategy rather than just its reward. A trader who understands drawdown sizes their risk to survive the bad stretches; one who ignores it eventually meets a losing run large enough to end the account.
What Drawdown Actually Measures
Drawdown is the decline in account equity from a peak to a subsequent trough, usually expressed as a percentage of the peak. If your account reaches $12,000 and then falls to $9,600 before making a new high, that's a drawdown of $2,400, or 20% of the peak.
The key word is peak. Drawdown is always measured from the highest point the account has previously reached, not from your starting balance and not from a round number. This matters because it captures how far you've fallen from the best your account has ever been — which is exactly the moment that feels worst and does the most psychological and mathematical damage. An account that grows from $10,000 to $15,000 and then slips to $12,000 is still up 20% overall, but it is in a 20% drawdown from its $15,000 peak, and it will not be "recovered" until it climbs back above $15,000.
Peak-to-Trough vs. Current Drawdown
There are two drawdown numbers worth separating. Current drawdown is how far below the most recent peak the account sits right now. Maximum drawdown is the largest peak-to-trough decline the account (or a strategy's backtest) has ever experienced — the worst it got at any point.
As the diagram shows, the account only counts as fully recovered once equity climbs back to the prior peak, not merely once it bounces off the low. A common mistake is to feel relief the moment an account stops falling and starts rising again — but if the peak was $15,000 and you've recovered from $10,500 back to $12,000, you're still in a 20% drawdown, not out of it. Maximum drawdown is the single number that tells you the deepest hole the strategy has dug, and therefore the size of the loss you need to be emotionally and financially prepared to sit through.
Why the Recovery Math Is Not Symmetric
The most dangerous property of drawdown is that the gain required to recover from it is always larger than the loss itself, and the gap widens fast as the drawdown deepens. This is the same asymmetry covered in Compounding and Position Sizing, and the formula is worth repeating:
Gain needed to recover = Drawdown ÷ (1 − Drawdown)
Lose 10%, and you need 11.1% to get back to even. Lose 20%, and you need 25%. Lose 50%, and you need a 100% gain — you must double the remaining money just to reach the old peak. Lose 75%, and recovery requires a 300% gain. The loss grows in a straight line while the required recovery curves upward, because each recovery gain is calculated on the smaller surviving balance. This is precisely why a deep drawdown is so much worse than a shallow one — it's not twice as bad to lose 50% instead of 25%, it's far more than twice as bad, because the climb back out steepens the deeper you go.
Maximum Drawdown as a Strategy Metric
When you evaluate a strategy — your own or one you're testing — maximum drawdown belongs right next to the profit figure, and often ahead of it. A strategy that returns 40% a year but suffered a 60% maximum drawdown along the way is far riskier than one that returns 20% with a 15% maximum drawdown, because the first one, at its worst moment, needed a 150% gain just to recover and would have been psychologically unbearable to hold. This is a core reason backtesting a strategy reports maximum drawdown as a headline statistic: the equity curve's smoothness and the depth of its worst decline tell you whether a strategy is actually tradeable by a human being, not just whether it's profitable on paper.
A Worked Example
Take a $10,000 account that grows to a $13,000 peak, then hits a rough patch and falls to $9,750 before recovering:
- Peak: $13,000.
- Trough: $9,750.
- Drawdown in dollars: $13,000 − $9,750 = $3,250.
- Drawdown in percent: $3,250 ÷ $13,000 = 25%.
- Gain needed to recover from the trough back to the $13,000 peak: $3,250 ÷ $9,750 = 33.3%.
So a 25% drawdown demands a 33% gain to erase — and notice the account is still up 30% on its original $10,000 deposit even at the trough, yet it's in a painful 25% drawdown from its peak. Both facts are true at once, which is exactly why traders track drawdown separately from total return: the account can be profitable overall and in a serious drawdown at the same time.
The Psychological Side of a Deep Drawdown
Drawdown isn't only a math problem — it's where most strategies actually die, because the trader abandons them at the worst possible moment. A long, deep drawdown is precisely when doubt, fear, and revenge trading peak, tempting a trader to abandon a sound plan, double their risk to "win it back faster," or jump to a new system right before the old one recovers. The defense is to know your strategy's historical maximum drawdown in advance, size your risk so that a drawdown of that depth is survivable both financially and emotionally, and treat reaching it as a normal, expected event rather than proof the strategy is broken. A drawdown you planned for is a bad week; a drawdown you never imagined is an account-ending panic.
Why This Matters
Drawdown is the honest measure of a strategy's risk, and its asymmetric recovery math is the mechanical reason that capital preservation matters more than chasing the biggest possible return. Keeping drawdowns shallow — through the 1-2% per-trade risk rule, position sizing, and not over-leveraging — keeps you on the flat, cheap part of the recovery curve, where an ordinary run of trades is enough to make new highs. Let a drawdown run deep and you need an extraordinary recovery just to break even, with a smaller balance to do it with. Understanding drawdown is understanding the difference between a business that survives its bad stretches and one that doesn't.