Calmar ratio
What is Calmar ratio?
The Calmar ratio compares annualized return with maximum drawdown, expressing return earned per unit of the deepest observed peak-to-trough loss.
Why the Calmar ratio matters
The ratio connects compounded growth with a loss measure investors experience directly. It is often used for hedge funds, managed futures, and strategies where drawdown control matters. Unlike volatility-based ratios, it focuses on the single worst observed decline, making the chosen history and treatment of recovery particularly important.
How it is calculated
A common form divides annualized return by the absolute value of maximum drawdown over the same evaluation window. Conventions vary in the return period, minimum history, and whether returns are gross or net. The calculation should use a consistent, sufficiently frequent valuation series so interim peaks and troughs are not missed.
Example
A strategy has a 12% annualized net return and a maximum drawdown of 20%, producing a Calmar ratio of 0.6. Another returns 9% with a 10% drawdown, producing 0.9. The second has delivered more historical return per unit of maximum drawdown, but the ratio does not predict its next drawdown.
How to interpret it
Higher is generally preferable for comparable strategies, dates, currencies, and fee conventions. Examine when the maximum drawdown occurred, how long recovery took, and whether the strategy or leverage changed afterward. A high ratio from a short record may simply mean no severe event has occurred in the sample.
Limitations
Maximum drawdown is one path-dependent observation and can change abruptly after a new loss. The ratio ignores all other drawdowns, liquidity, tail shape, and intra-period movement. Smoothed or infrequent valuations can understate the denominator. Negative annualized return or no observed drawdown can also produce results that are difficult or meaningless to interpret.
Practical checklist
Use daily or suitably frequent total returns, define the evaluation window, and calculate return and drawdown on the same net or gross basis. Display the underwater chart and recovery duration with the ratio. Compare several rolling windows and stress scenarios. Investigate valuation smoothing, leverage, and structural changes before ranking strategies from a single historical Calmar value or drawing firm conclusions about future downside protection.