Investment Principles, Risk and Return
Domain 2: Investment principles, risk and return
This domain tests the relationship between risk and expected return, the difference between real and nominal outcomes, and the principles of diversification. Candidates must distinguish volatility from permanent loss and risk tolerance from capacity for loss.
Core principles
- Investors require compensation for risk. The risk-free rate plus premiums for inflation, credit, liquidity and equity risk builds expected return.
- Nominal return includes inflation; real return adjusts for it. Approximate real return = nominal return − inflation; the Fisher relationship is more precise: (1 + nominal)/(1 + inflation) − 1.
- Total return combines income and capital growth. Arithmetic average return overstates compound wealth when returns are volatile; geometric return is the compound growth rate.
- Diversification reduces unsystematic risk. Systematic risk remains and is measured by beta relative to the market.
- Risk tolerance is willingness to take risk; capacity for loss is ability to absorb it. Both must be assessed.
Measuring risk
- Volatility (standard deviation) measures dispersion of returns and treats upside and downside equally.
- Beta measures sensitivity to market moves; a beta above 1 amplifies market risk.
- Correlation drives diversification: the lower the correlation, the greater the risk reduction from combining assets.
- Time horizon matters: short horizons need liquidity and capital stability; long horizons can tolerate more volatility but not necessarily more permanent loss.
Worked example
A portfolio is 60% equities with expected return 8% and 40% bonds with expected return 3%. Expected portfolio return = (0.60 × 8%) + (0.40 × 3%) = 6.0%. With inflation at 2.5%, real return = (1.06/1.025) − 1 = 3.41%, not 3.5%. If equity volatility is 15% and bond volatility 5%, the weighted average volatility is 11%, but portfolio volatility will be lower if correlation is below 1. Expected return is weighted; risk is not, because of diversification.
Traps
- Treating a high risk-tolerance score as permission to ignore a short-term goal or limited capacity for loss.
- Using past volatility as a guarantee of future risk, or ignoring liquidity risk.
- Confusing arithmetic and geometric returns when assessing long-run wealth.
- Quoting nominal returns when the client’s objective is inflation-adjusted.
Key points
- Expected return is weighted; portfolio risk depends on correlations.
- Real return adjusts nominal return for inflation using the Fisher relationship.
- Diversification removes unsystematic, not systematic, risk.
- Risk tolerance and capacity for loss are separate assessments.
- Geometric return reflects compound wealth better than arithmetic average.