Sharpe, Sortino and Risk-Adjusted Return Metrics

Two managers each return twelve per cent a year. One did it smoothly; the other lurched through stomach-churning drawdowns to get there. Raw return treats them as identical, which is why allocators almost never look at return alone. Risk-adjusted metrics exist to answer the real question: how much risk did a manager take to earn each unit of return, and was it worth it?

A high return with a low Sharpe is a warning, not a triumph. The ratio tells you how much volatility the manager put investors through to get there.Jeffrey Shaul, Director at CV5 Capital

Why raw returns mislead

Return is only half of the picture because it ignores the path. A strategy that compounds steadily and one that swings violently can post the same headline number while offering completely different experiences to an investor, especially one who might need to redeem at the wrong moment. Risk-adjusted measures normalise return by the risk taken, allowing strategies with different volatility profiles to be compared on a more honest basis.

Sharpe ratio: definition and weaknesses

The Sharpe ratio divides a strategy's return above the risk-free rate by its volatility, the standard deviation of returns. A higher Sharpe means more return per unit of total volatility. Its weakness is that it treats upside and downside volatility identically, penalising a manager for big positive months as much as big negative ones. It also assumes returns are reasonably well-behaved, which is often untrue for strategies with optionality, leverage or illiquidity, where a smooth-looking Sharpe can mask real tail risk.

Sortino and downside-only risk

The Sortino ratio addresses the most obvious flaw by measuring only downside deviation, the volatility of losses, rather than total volatility. Because investors do not lose sleep over upside surprises, Sortino better reflects how risk is actually experienced. For strategies with asymmetric return profiles it is often more informative than Sharpe, though it shares the same dependence on a representative sample of returns.

Calmar and drawdown-based measures

Drawdown-based measures take a different angle, comparing return to the worst peak-to-trough loss. The Calmar ratio, for example, divides annualised return by the maximum drawdown over a period. These measures speak directly to capital preservation and to the question an allocation committee actually asks: how bad did it get, and how long did recovery take? They are particularly useful for strategies where the maximum drawdown, not month-to-month volatility, is the binding risk.

Using ratios in real ODD

No single ratio is sufficient, and all of them can be gamed by a short or flattering sample. In real operational due diligence, allocators look at several measures together, over meaningful and consistent periods, net of fees, and they probe how the numbers were produced, smoothed marks, survivorship and period selection are the usual culprits. The metrics are a starting point for questions, not a verdict. For managers, presenting a consistent, honestly-sampled set of risk-adjusted figures signals exactly the institutional discipline allocators are testing for. For the wider context, see our guide to the institutional due diligence process.

Key Takeaways

Frequently Asked Questions

What does the Sharpe ratio measure?

It measures return above the risk-free rate per unit of total volatility. A higher Sharpe indicates more return for the volatility taken, though it treats upside and downside volatility the same.

How is Sortino different from Sharpe?

Sortino uses only downside deviation rather than total volatility, so it does not penalise upside moves. It often better reflects how investors actually experience risk.

Why look at drawdown-based ratios?

Measures such as Calmar compare return to the worst peak-to-trough loss, speaking directly to capital preservation and recovery, which matters where maximum drawdown is the binding risk.

This article is produced by CV5 Capital for informational purposes only and does not constitute legal, regulatory, tax or investment advice, and nothing here is a recommendation to make any investment. Fund managers should obtain independent professional advice based on their specific structure, investors, strategy and regulatory obligations. CV5 Capital is registered with the Cayman Islands Monetary Authority (CIMA Registration No. 1885380, LEI: 984500C44B2KFE900490).