Direct answer: “How to calculate profitability ratio forex” (via Kaufman Efficiency Ratio)
A “profitability ratio” is not a single universal forex formula, but one common efficiency-based way to quantify the idea of profitability from price movement is to use Kaufman Efficiency Ratio (KER). KER is calculated from historical prices over a chosen lookback period and compares net change to total movement.
In practical terms, you compute KER for a fixed window of N periods, using the same price series (for example, close-to-close). A higher KER indicates that price traveled more directly from start to end of the window; a lower KER indicates more back-and-forth movement.
Explanation: definitions, inputs, and calculation mechanics
To calculate Kaufman Efficiency Ratio:
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Choose the lookback period (N). This is the number of bars (time steps) in the window you evaluate. N is an input you control; it changes the sensitivity of the measure.
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Pick the price series. KER is computed from price values (often the closing price). The formula expects a consistent series across the entire calculation.
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Compute net movement. Let Price(t) be the price at the end of the window, and Price(t−N) the price at the start. Net movement is:
- | Price(t) − Price(t−N) |
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Compute total movement. Add the absolute changes between consecutive prices across the window:
- Σ_{i=1..N} | Price(t−(i−1)) − Price(t−i) |
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Compute the ratio. KER is typically expressed as:
- KER = Net movement / Total movement
Simple check of the interpretation
- If price moves smoothly in one direction, net movement will be relatively large compared to total movement, so KER tends to be higher.
- If price alternates direction frequently, net movement shrinks while total movement grows, so KER tends to be lower.
You can treat this as an “efficiency/profitability proxy” because it measures how directional the realized movement was over the window. It does not compute profit directly.
Example-style walkthrough (without predicting outcomes)
Assume you work with a consistent price series and want KER over N periods.
- Take Price(t−N) as the first value in the window and Price(t) as the last value.
- Net movement is the absolute difference between those two values.
- Total movement is the sum of absolute bar-to-bar changes inside the window.
- Divide net movement by total movement.
If net movement is small because the price ends near where it started, KER will be low. If net movement is large relative to the sum of all the intermediate swings, KER will be higher.
Because the result depends on your chosen N and your chosen price series (e.g., close), two analysts using different inputs can calculate different KER values from the same underlying asset.
Limitations and uncertainties (what you can and cannot infer)
KER helps quantify directional efficiency of past movement, but it has important limitations when someone asks about “profitability”:
- Not a future-return metric. KER is computed from past price changes. It does not directly measure future returns and cannot confirm that profits will follow.
- Sensitivity to assumptions. The result changes with the chosen lookback period N and the chosen price series.
- Market microstructure effects. In real trading data, sampling frequency and price availability (for example, how prices are recorded per bar) can affect the absolute changes used in total movement.
If your goal is “profitability,” it is safer to treat KER as an independent historical descriptive indicator of how directional price action was over the selected window, rather than as a numeric guarantee of outcomes.
Relevant comparison and verification
To verify your calculation independently: