Drawdown: the number that decides whether you are still there in a year

Two systems return 20% a year. The first never sits more than 3% below its own high-water mark. The second gets there after eleven months with the account 40% underwater.

On a year-end statement they look identical. In real life almost nobody survives the second, because eleven months is long enough to decide the thing is broken, switch it off, and miss the recovery. The number that separates them is drawdown, the most useful figure on any performance report. It is more useful than the return, by a wide margin.

The definition, with nothing added

Drawdown is the drop from a peak in your account equity to the trough that follows it, before a new peak is made. That is the whole definition.

Say an account runs $50,000, then $53,000, then $51,000, then $49,500, then back to $54,000. Peak $53,000, trough $49,500, drawdown $3,500. Once equity passes $53,000 the clock resets. Maximum drawdown is the deepest of those episodes across the history.

Two things follow that people get wrong constantly. Drawdown is measured against your own equity high, not your starting balance, so an account up 40% on the year can still be in a painful one. And it is measured on equity, so a report built on closed trades understates what you watched on the screen.

Max drawdown is not the number you will experience

Maximum drawdown is one observation: the worst thing that happened once, in a specific sequence of history. It says almost nothing about a normal bad week.

Average drawdown, the mean depth across every peak-to-trough episode in the record, describes your actual life with a system. It is almost always far smaller than the maximum, and it is the one to check your tolerance against, because you will meet it dozens of times a year and the maximum maybe once.

The maximum drawdown in any backtest is simply the worst one that has happened so far.

Time underwater is the part that actually breaks people

Depth gets all the attention. Duration does the damage.

Time underwater is how long the account spends below a previous high before making a new one. A 6% drawdown that recovers in nine days is a non-event. The same 6% grinding sideways for five months is what gets systems switched off. That is long enough for doubt to become a decision.

Nobody quits on the day of the biggest loss. People quit on week fourteen of nothing happening, when the story in their head has moved from "this is a rough patch" to "this used to work and now it doesn't." So look for two duration figures alongside the drawdown: longest time underwater and losing months. A seller who publishes a max drawdown but no recovery time has shown you the easier half of the picture.

Why publishing a drawdown is a credibility signal

It is still a claim, not a proof. The point of a reproducible backtest is that you can run it yourself in the Strategy Analyzer inside NinjaTrader 8 and check that the drawdown you get is the one you were shown. That is the difference between a number you verify and a number you trust, and the whole argument of what a trading bot actually is.

How to use the number before you buy

• Compare it to the account rule, not the profit. Not "is this drawdown small?" but "does it fit inside the threshold on the account I intend to trade?" Often it does not, and the answer is a bigger account or fewer contracts.
• Scale it with contracts. Two contracts means roughly double the dollar drawdown with the same rulebook underneath. Sizing up multiplies the pain as fast as the profit.
• Decide your quit rule now. Write down the drawdown at which you would conclude the system has stopped behaving like its history. A number chosen in advance is a decision; one chosen during a bad week is a reaction.

Frequently asked questions

What is a good maximum drawdown?

There is no universal threshold, because it only means something relative to the return, the account size and the account rules. A more useful test is the ratio of net profit to maximum drawdown, sometimes called the recovery factor, plus whether the drawdown fits inside the limits of the account you plan to trade. A modest drawdown you can sit through beats a better return you abandon in month three.

What is the difference between drawdown and a losing streak?

A losing streak counts consecutive losing trades. A drawdown measures money lost from a peak, and needs no consecutive losses at all: alternating small wins and larger losses produce a drawdown with no streak in it. Streaks explain part of a drawdown, but the drawdown determines whether an account survives.

Should I turn a system off when it hits its maximum drawdown?

Exceeding a historical maximum is a reason to look closely, not an automatic stop. What matters is whether the system still behaves like itself (similar trade frequency, similar average win and loss, similar hit rate) or whether something has changed. Decide the rule in advance and in writing; the worst time to invent one is inside the drawdown that prompted the question.

Educational content, not investment advice. Trading futures involves substantial risk of loss and is not suitable for every investor. Any reference to Algomyth results is hypothetical, simulated over historical data, and shown in full on the performance page; past performance does not guarantee future results.