Return % Alone Is Meaningless Without Risk
A system that makes 50% but has 60% drawdowns is worse than one making 10% with 5% drawdowns. Sharpe ratio measures this trade-off scientifically.
Understanding Sharpe Ratio
Simple definition: Return per unit of volatility.
- Formula: (Average return - Risk-free rate) / Standard deviation
- English: How much profit per unit of risk taken
- Risk-free rate: Treasury yield (~4-5% in 2026)
- Standard deviation: Volatility of your returns
Interpreting Sharpe Ratios
What different ratios mean:
- Below 0: You're losing money (negative return). Clearly bad.
- 0-0.5: You're barely beating risk-free rate. Not worth the volatility.
- 0.5-1.0: Decent, but could be better. Most traders fall here.
- 1.0-2.0: Good. You're getting paid well for risk taken.
- Above 2.0: Excellent. Rare for individual traders.
Real-World Examples
Three portfolios, different Sharpe ratios:
- System A: 20% annual return, 30% volatility -> Sharpe = 0.53 (mediocre)
- System B: 12% annual return, 8% volatility -> Sharpe = 1.0 (good)
- System C: 25% annual return, 10% volatility -> Sharpe = 2.1 (excellent)
System C beats A and B despite being different. Why? Better risk-adjusted returns.
Using Sharpe Ratio for System Comparison
Comparing two trading systems?
- System 1: 15% return, Sharpe 0.8
- System 2: 12% return, Sharpe 1.2
System 2 wins. It makes slightly less but with much better risk control. Over 30 years, System 2 compounds better.
Improving Your Sharpe Ratio
How to increase your risk-adjusted returns:
- Lower volatility: Take less risk per trade (smaller position size)
- Increase returns: Trade higher-conviction setups only
- Reduce drawdowns: Tighter stops and position limits
- Diversify: Spread risk across more uncorrelated assets
The Sharpe Edge
Traders focused on Sharpe ratio build sustainable systems. Traders chasing raw returns build accounts that get wiped out. Sharpe forces you to think about compounding.