Fair Rate of Return Calculator
Calculation Results (CAPM)
What is a Fair Rate of Return?
A Fair Rate of Return represents the minimum percentage of profit an investor requires to justify the risk of a specific investment. Unlike simple interest or yield, the fair rate considers opportunity cost—what you could earn elsewhere with a similar risk profile.
This calculator uses the Capital Asset Pricing Model (CAPM), the standard financial framework for determining the appropriate required rate of return of an asset. It helps investors decide if a stock or project is worth the risk.
How the Calculation Works
The calculation relies on three distinct variables to determine what is "fair" for the level of risk undertaken:
- Risk-Free Rate ($R_f$): The theoretical return of an investment with zero risk. In practice, the yield on a 10-year US Treasury bond is often used as the proxy.
- Beta ($\beta$): A measure of a stock's volatility in relation to the overall market.
- $\beta = 1.0$: The asset moves in sync with the market.
- $\beta > 1.0$: The asset is more volatile (riskier) than the market.
- $\beta < 1.0$: The asset is more stable (less risky) than the market.
- Expected Market Return ($R_m$): The average return expected from the broader market (like the S&P 500) over a long period. Historically, this is often estimated between 8% and 10%.
The Formula
The mathematical formula for the Fair Rate of Return ($R_e$) is:
Fair Return = Risk-Free Rate + Beta × (Market Return – Risk-Free Rate)
The term (Market Return – Risk-Free Rate) is known as the Market Risk Premium. Multiplying this by Beta adjusts the premium based on the specific asset's volatility.
Example Calculation
Let's say you are analyzing a tech stock with the following metrics:
- Risk-Free Rate: 4.0% (Current Treasury Yield)
- Beta: 1.5 (High Volatility)
- Market Return: 10.0% (Historical Average)
First, we calculate the Market Risk Premium: $10.0\% – 4.0\% = 6.0\%$.
Next, we adjust for the specific asset's risk: $1.5 \times 6.0\% = 9.0\%$.
Finally, we add the risk-free base rate: $4.0\% + 9.0\% = 13.0\%$.
In this scenario, a 13.0% return is the "fair" rate. If you expect the stock to only return 8%, it is undervalued relative to its risk. If you expect it to return 15%, it may be an attractive investment.