Strategy Evaluation Guide: Expectancy, Drawdown and Risk-Adjusted Returns

Win rate is not everything

A strategy with a 40% win rate and a high payoff ratio can beat one with an 80% win rate and large average losers. What decides the long-term outcome is expectancy, not win rate alone.

Expectancy = win rate × average win − (1 − win rate) × average loss. Positive expectancy compounds; negative expectancy means even a high win rate is just waiting for one big loss.

Profit factor: total wins over total losses

Profit factor = gross profit ÷ gross loss. Above 1 means net profit; a common rule of thumb wants it above ~1.5 for robustness. The closer it is to 1, the more the result depends on a few trades.

Profit factor and expectancy complement each other: expectancy answers “how much per trade”, profit factor answers “how many times wins cover losses overall”.

Max drawdown: how much you lose is the key number

Max drawdown is the largest peak-to-trough decline of the account. Its sting is in the recovery math: a 20% loss needs +25% to recover, and a 50% loss needs +100%.

When evaluating a strategy, look beyond total return at how deep and how long the equity was underwater — and whether that fits your capital and temperament.

Sharpe and Calmar: returns weighed against risk

Sharpe = (annualized return − risk-free rate) ÷ annualized volatility; it measures excess return per unit of volatility. Calmar = annualized return ÷ max drawdown; it measures annualized return per unit of drawdown endured.

Both help compare risk-adjusted returns across strategies. With short samples these ratios swing a lot, so draw conclusions only from records that include bull, bear and sideways regimes.

Evaluate after costs and slippage

Backtest gross profit shrinks in live trading because of fees, funding and slippage — high-frequency styles shrink the most. Always evaluate on an after-fee equity basis and leave a slippage buffer.

Curves fitted to past data often decay fast out of sample. Keeping a conservative margin in the metrics beats chasing the prettiest backtest.

Reviewing a strategy with metrics

• Use the expectancy calculator with win rate, average win and average loss to confirm expectancy is positive.
• Use the profit factor calculator to check whether wins cover losses by a robust margin.
• Use the max drawdown calculator to record peak-to-trough severity and confirm you can tolerate it.
• Compare strategies side by side with the Sharpe ratio and Calmar ratio calculators on a risk-adjusted basis.
• Compute every metric on after-fee equity and leave room for slippage.

This guide is for educational purposes only and is not investment advice. Always follow your exchange's actual margin, liquidation and fee rules, and keep a buffer for extreme market moves.

If you want to cut down on manual work, the same flow can be executed automatically under the same rules by a quant system such as CubeQuants.