Calculate the Expected Rate of Return (CAPM) based on market risk and volatility.
%
Typically the yield on 10-Year Treasury Bonds.
Measure of stock volatility relative to the market (1.0 = Market Avg).
%
Historical average return of the S&P 500 or target index.
Expected Rate of Return
0.00%
What is the Expected Rate of Return on a Stock?
The expected rate of return is a key financial metric used by investors to estimate the profit or loss anticipated on an investment that has known or anticipated rates of risk. Unlike simple ROI which looks backward, the expected rate of return is a forward-looking calculation based on financial models.
This calculator uses the Capital Asset Pricing Model (CAPM), which is the standard method for determining the appropriate required rate of return of an asset given that asset's non-diversifiable risk (Beta).
The CAPM Formula
The formula used in this calculation is:
E(Ri) = Rf + βi (E(Rm) – Rf)
Rf (Risk-Free Rate): The theoretical rate of return of an investment with zero risk. In practice, the yield on 10-year U.S. Treasury bonds is often used as a proxy.
β (Beta): A measure of a stock's volatility in relation to the overall market. A beta of 1.0 indicates the stock moves with the market. A beta greater than 1.0 indicates higher volatility (and theoretically higher potential return/risk).
E(Rm) (Expected Market Return): The average return of the market portfolio, such as the S&P 500. Historically, this is often estimated between 8% and 10%.
(E(Rm) – Rf): This is known as the Market Risk Premium. It represents the extra return investors demand for taking on the risk of the stock market over a risk-free asset.
Example Calculation
Let's assume you are analyzing a tech stock with the following metrics:
This means that, given the risk profile of this specific stock (1.5 Beta), a rational investor should expect (or require) a 13% return to justify holding it.
How to Interpret Beta
Beta < 1: Defensive stocks (e.g., Utilities, Consumer Staples). These are less volatile than the market.
Beta = 1: The stock moves exactly in sync with the market index.
Beta > 1: Aggressive stocks (e.g., Tech, Biotech). These are more volatile than the market. High beta implies higher risk but higher expected returns.
Beta < 0: Negative beta assets (e.g., Gold, Inverse ETFs) generally move opposite to the market.
function calculateExpectedReturn() {
// Get input values
var rfRateInput = document.getElementById('riskFreeRate').value;
var betaInput = document.getElementById('stockBeta').value;
var marketReturnInput = document.getElementById('marketReturn').value;
// Validation: Check if inputs are empty
if (rfRateInput === "" || betaInput === "" || marketReturnInput === "") {
alert("Please fill in all fields (Risk-Free Rate, Beta, and Market Return) to calculate.");
return;
}
// Parse values
var rf = parseFloat(rfRateInput);
var beta = parseFloat(betaInput);
var rm = parseFloat(marketReturnInput);
// Validation: Check for NaN
if (isNaN(rf) || isNaN(beta) || isNaN(rm)) {
alert("Please enter valid numbers for all fields.");
return;
}
// CAPM Calculation
// Formula: E(R) = Rf + Beta * (Rm – Rf)
var marketRiskPremium = rm – rf;
var riskPremium = beta * marketRiskPremium;
var expectedReturn = rf + riskPremium;
// Display Result
var resultBox = document.getElementById('resultBox');
var finalReturnDisplay = document.getElementById('finalReturn');
var explanationDisplay = document.getElementById('resultExplanation');
resultBox.style.display = "block";
finalReturnDisplay.innerHTML = expectedReturn.toFixed(2) + "%";
// Generate dynamic explanation based on Beta
var explanationText = "";
if (beta > 1) {
explanationText = "This stock has a Beta of " + beta + ", indicating it is more volatile than the market. Investors require a premium of " + riskPremium.toFixed(2) + "% over the risk-free rate to hold this asset.";
} else if (beta 0) {
explanationText = "This stock has a Beta of " + beta + ", indicating it is less volatile than the market. It is considered a defensive holding with a lower required return.";
} else if (beta === 1) {
explanationText = "This stock moves in perfect correlation with the market average.";
} else {
explanationText = "This stock has a negative or zero Beta, implying it may move independently or inversely to the market.";
}
explanationDisplay.innerHTML = explanationText;
}