[fv_keypoints]
– Risk a fixed small percentage of equity per trade and let volatility determine size
– Stop distance should come from market structure and ATR, never from a desired position size
– Correlated positions are one position; size them as such
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Almost every serious discussion of trading eventually arrives at the same conclusion: entries matter far less than most people believe, and sizing matters far more. The reason is arithmetic. A trader who is right sixty percent of the time will still lose money if the losses are larger than the wins, and a trader who is right forty percent of the time can compound steadily if they are not.
Start from risk, not from size
The common mistake is to decide how many lots to trade and then place a stop wherever it fits. That inverts the logic. The correct sequence is:
- Decide the maximum percentage of account equity you are willing to lose on this trade. For most people this sits between 0.5% and 1%.
- Identify where the trade idea is objectively wrong on the chart. That level defines your stop distance.
- Divide risk capital by stop distance to get position size.
The size that comes out is the size. If it feels too small to be worth taking, the problem is the expectation, not the arithmetic.
Let volatility set the stop
A fixed twenty-pip stop is a different amount of risk in a quiet market than in a violent one. Average true range gives you a volatility-adjusted measure: a stop placed at one to two times the current daily ATR beyond your invalidation level will survive ordinary noise, while a stop inside the daily range is essentially a coin flip on whether you get removed before the idea has a chance.
Correlation is hidden leverage
Three separate one-percent risks in EUR/USD, GBP/USD and AUD/USD is not three percent of diversified risk. It is close to three percent riding on a single dollar view. The same applies to being long gold, long silver and long miners, or long several altcoins simultaneously. Before adding a position, ask what would have to be true for all your open trades to lose at once. If the answer is “one thing”, you have one trade.
Drawdown mathematics
Losses compound against you asymmetrically. A 10% drawdown requires an 11% gain to recover; a 30% drawdown requires 43%; a 50% drawdown requires 100%. This is the entire argument for small per-trade risk. It is not caution for its own sake — it is the recognition that deep holes are mathematically expensive to climb out of and psychologically expensive to trade out of.
Scaling rules worth having
Two simple policies prevent most account-ending events. First, a daily loss limit: once you are down a defined amount, you stop for the day, without exception. Second, an equity-based throttle: reduce per-trade risk while in drawdown and only restore it after recovering. Both remove the decision from you at exactly the moment your judgement is least reliable.
The uncomfortable conclusion
Correct position sizing will make your good months less exciting. That is the trade. The purpose is to guarantee you are still trading in two years, at which point a modest edge applied consistently has had time to compound.