A Sharpe ratio of 1.17 sounds good. A beta of 0.61 sounds safe. Neither statement means anything until you know what the benchmark did over the same period, and one of them turns out to be wrong.
Here are 2 real portfolios, each read off its risk panel on a specific date. They are opposite in almost every respect, and between them they break the 2 assumptions most people carry about these numbers.
| Metric | Portfolio A, June 8 2026 | Portfolio B, August 18 2026 |
|---|---|---|
| Beta | 0.61 (benchmark 1.00) | 2.75 (benchmark 1.00) |
| Sharpe | 0.70 (benchmark 1.13) | 1.17 (benchmark 0.99) |
| Sortino | 1.13 (benchmark 1.46) | 2.55 (benchmark 1.31) |
| Max drawdown | -20.03% (benchmark -13.72%) | -48.59% (benchmark -19.00%) |
Portfolio A carried about 60% of the market's volatility and still lost to it on both risk-adjusted measures, while falling further than the index did. Portfolio B carried nearly 3 times the market's volatility, beat the index on both measures, and put its owner through a 48.59% decline to get there. Low beta did not mean safer. A winning Sharpe did not mean a comfortable ride.
The 4 numbers in one line each
- Beta: how much of the market's movement you are carrying. Not a quality score.
- Sharpe: excess return per unit of total volatility, upside and downside alike.
- Sortino: the same, but only downside volatility counts against you.
- Max drawdown: the worst peak-to-trough fall, and the one you have to sit through.
- None of the 4 means anything without the benchmark's own value beside it.
Beta: how much market you are holding
Beta is the covariance of your returns with the benchmark's, divided by the benchmark's variance. A beta of 1.0 means you move with the market. Portfolio A at 0.61 moves about 61% as much; Portfolio B at 2.75 moves nearly 3 times as much.
The common error is reading beta as a safety rating. It is a measure of sensitivity to one thing: the index. A portfolio can have a low beta and still be dangerous, because beta says nothing about the risks that are specific to what you own. A single-stock position in a company facing a patent cliff can have a modest beta right up until the ruling lands. Portfolio A is the mild version of this: a beta of 0.61 alongside a drawdown worse than the market's.
Sharpe: return per unit of total volatility
Sharpe takes your average daily return, subtracts the risk-free rate, divides by the standard deviation of that excess return, and annualises by multiplying by the square root of 252 trading days. It answers a single question: for each unit of wobble you accepted, how much return did you get above cash.
The comparison is what makes it readable. Portfolio B's 1.17 against a benchmark of 0.99 says it was paid better per unit of risk than the index over that period. Portfolio A's 0.70 against 1.13 says the opposite, and says it despite the lower beta. If a platform shows you a Sharpe ratio with no benchmark beside it, you are being shown half a number.
Sortino: only the downside counts against you
Sortino uses the same excess return in the numerator and changes the denominator to the standard deviation of negative days only. Upside volatility stops being a penalty.
The useful trick is to read Sortino against Sharpe rather than in isolation. The wider the gap, the more of the portfolio's volatility sits on the upside. Portfolio B's Sortino is 2.18 times its Sharpe, against 1.32 for its benchmark, so its swings skew upward considerably more than the index's do. Portfolio A shows the same effect more mildly at 1.61 against 1.29.
That is a real distinction, and also a warning. A high Sortino can flatter a portfolio that has simply not met its bad period yet, because a denominator built only from down days is estimated from fewer observations than one built from all of them.
Max drawdown: the number you have to live through
Max drawdown is the worst peak-to-trough decline over the period: the largest fall from a running high. Unlike the ratios it is not a statistical abstraction. It is an experience with a date on it.
It is also the number where the arithmetic is least forgiving, because recovering a loss takes a bigger gain than the loss itself. Portfolio A's -20.03% needs a 25.0% gain to get back to even. Portfolio B's -48.59% needs 94.5%. Nearly a double, just to return to the previous high.
A ratio describes the past efficiently. A drawdown describes what you would have had to sit through, and whether you would actually have stayed.
Read against the benchmark, Portfolio A fell 1.46 times as far as the index and Portfolio B 2.56 times as far. Portfolio B's ratios are genuinely better; its drawdown is the price of them, and no risk-adjusted number will make that fall feel like 48.59% divided by anything.
Reading the 4 together
Taken one at a time these numbers mislead. Taken together they describe a strategy.
- Beta tells you where the risk comes from. High beta means the market is the main driver. Low beta with poor ratios, like Portfolio A, means the risk is coming from something else, and it is worth finding out what.
- Sharpe tells you whether you were paid for it, against the same period's benchmark and never in isolation.
- Sortino against Sharpe tells you which direction the volatility ran. A wide gap is upside skew; a narrow gap means the wobble was symmetric.
- Drawdown tells you whether the strategy is one you could actually hold. A plan you abandon at the bottom has an expected return of whatever you locked in when you sold.
Neither portfolio here is better than the other in any absolute sense. A is defensive and was not compensated for it over that period. B was compensated well and demanded a great deal of tolerance. Which one is appropriate is a question about you, not about the ratios.
Why the convention matters as much as the number
These metrics are not standardised across the industry, and small definitional choices move them.
| Choice | Why it changes the answer |
|---|---|
| Risk-free rate | Sharpe subtracts it before dividing. Finapolis uses 4% a year, divided across 252 trading days |
| Population or sample sigma | Dividing by n or by n minus 1 gives 2 different answers on the same returns |
| Return frequency | Daily returns annualised by root-252 do not give the same figure as monthly returns annualised by root-12 |
| Period | Every one of these numbers is period-dependent, which is why 2 portfolios show different benchmark values |
None of these choices is wrong. What is wrong is comparing a Sharpe ratio from one source with a Sharpe ratio from another and assuming they were built the same way. If a platform will not tell you its risk-free rate and its sigma convention, its ratio is not comparable to anything.
When you benchmark a portfolio, use the same source for both sides of the comparison and the same period for both. That is why the risk panel prints your value and the benchmark's together rather than leaving you to find the second number.
Where these numbers live
All 4 sit on the Performance tab of the Portfolio page, each printed next to the benchmark's own value with an arrow showing which way you are relative to it. The same tab carries a monthly returns table that shows the capital each period's return was divided by, so the return feeding these ratios can be checked rather than assumed.
The Backtest tab reports the same family of measures over a historical period, adding Calmar, which is annual growth divided by the absolute maximum drawdown, and turns the trade-off in this article into a single figure.
FAQ
Is a higher Sharpe ratio always better?
Better over the measured period, against the same benchmark, computed the same way. It says nothing about whether the next period resembles the last one, and it does not describe the drawdown you would have sat through.
What is a good Sharpe ratio?
The question is missing its second half. The only useful form is "good compared with what", which is why these are always shown against the benchmark's value for the same window. Portfolio B's 1.17 beats its benchmark's 0.99; Portfolio A's 0.70 loses to its benchmark's 1.13. The same number can be either.
Why do the 2 portfolios show different benchmark figures?
Because they cover different periods. The benchmark's Sharpe, Sortino and drawdown are measured over the same window as the portfolio they are shown beside, so they move as the window moves. Only beta's benchmark value is fixed, at 1.00 by definition.
Does a low beta mean my portfolio is defensive?
It means it is less sensitive to the index. Portfolio A had a beta of 0.61 and a drawdown worse than the market's, which is the counterexample. Beta captures market risk, not the risks specific to what you hold.
Why does recovering a drawdown take a bigger gain than the fall?
Because the gain is computed on the smaller balance left after the fall. Losing 50% leaves you needing 100% to get back. Losing 48.59% leaves you needing 94.5%.
Should I just pick the portfolio with the better ratios?
That is your call to make, and these numbers are inputs to it rather than an answer. Portfolio B has the better ratios and a drawdown 2.56 times the index's. Whether that is acceptable depends on your horizon and on what you would actually do at the bottom.
