Personal Rate of Return Calculator
The Personal Rate of Return (PRR) is a crucial metric for understanding the performance of your individual investments over a specific period. It measures the actual percentage gain or loss on an investment, taking into account all cash inflows and outflows. Unlike simple percentage gains, PRR accounts for the timing and amount of money you've put into and taken out of an investment, providing a more accurate picture of your investment's profitability.
function calculatePRR() {
var initialInvestment = parseFloat(document.getElementById("initialInvestment").value);
var finalInvestment = parseFloat(document.getElementById("finalInvestment").value);
var contributions = parseFloat(document.getElementById("contributions").value);
var withdrawals = parseFloat(document.getElementById("withdrawals").value);
var timePeriod = parseFloat(document.getElementById("timePeriod").value);
var resultDiv = document.getElementById("result");
if (isNaN(initialInvestment) || isNaN(finalInvestment) || isNaN(contributions) || isNaN(withdrawals) || isNaN(timePeriod)) {
resultDiv.innerHTML = "Please enter valid numbers for all fields.";
return;
}
if (timePeriod <= 0) {
resultDiv.innerHTML = "Time period must be greater than zero.";
return;
}
// PRR = [ (Final Value – Initial Value + Withdrawals – Contributions) / (Initial Value + Contributions) ] * 100
// This is a simplified calculation. A more precise PRR often involves the Internal Rate of Return (IRR)
// which accounts for the timing of cash flows and is more complex to calculate without specialized libraries.
// This calculation provides a good approximation for educational purposes.
var netGainOrLoss = finalInvestment – initialInvestment + withdrawals – contributions;
var totalInvestment = initialInvestment + contributions;
if (totalInvestment === 0) {
resultDiv.innerHTML = "Total investment (Initial Investment + Contributions) cannot be zero.";
return;
}
var rateOfReturn = (netGainOrLoss / totalInvestment) * 100;
resultDiv.innerHTML = "Your approximate Personal Rate of Return is:
" + rateOfReturn.toFixed(2) + "% (over " + timePeriod + " years)";
}
.calculator-container {
font-family: sans-serif;
max-width: 600px;
margin: 20px auto;
padding: 20px;
border: 1px solid #ddd;
border-radius: 8px;
background-color: #f9f9f9;
}
.calculator-inputs {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
gap: 15px;
margin-bottom: 20px;
}
.input-group {
display: flex;
flex-direction: column;
}
.input-group label {
margin-bottom: 5px;
font-weight: bold;
color: #333;
}
.input-group input {
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
box-sizing: border-box;
}
.calculator-inputs button {
grid-column: 1 / -1;
padding: 12px 20px;
background-color: #007bff;
color: white;
border: none;
border-radius: 4px;
cursor: pointer;
font-size: 16px;
transition: background-color 0.3s ease;
}
.calculator-inputs button:hover {
background-color: #0056b3;
}
.calculator-result {
margin-top: 20px;
padding: 15px;
background-color: #e9ecef;
border: 1px solid #ced4da;
border-radius: 4px;
text-align: center;
font-size: 18px;
color: #495057;
}
.calculator-result strong {
color: #28a745;
}