Treasury Bill Rate Calculator
A Treasury Bill (T-bill) is a short-term debt security issued by the U.S. Department of the Treasury. T-bills are sold at a discount to their face value and pay the face value at maturity, with the difference representing the interest earned. They are considered one of the safest investments because they are backed by the U.S. government.
The T-bill rate is typically quoted on a discount basis. This calculator helps you determine the actual yield you would receive.
function calculateTBillRate() {
var faceValue = parseFloat(document.getElementById("faceValue").value);
var purchasePrice = parseFloat(document.getElementById("purchasePrice").value);
var daysToMaturity = parseFloat(document.getElementById("daysToMaturity").value);
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = "; // Clear previous results
if (isNaN(faceValue) || isNaN(purchasePrice) || isNaN(daysToMaturity) || faceValue <= 0 || purchasePrice <= 0 || daysToMaturity = faceValue) {
resultDiv.innerHTML = 'Purchase price should be less than face value for a discount instrument.';
return;
}
// Calculate the discount amount
var discountAmount = faceValue – purchasePrice;
// Calculate the holding period yield
var holdingPeriodYield = discountAmount / purchasePrice;
// Calculate the annualized yield (coupon equivalent yield)
// This formula converts the holding period yield to an annualized rate assuming a 360-day year, which is standard for T-bills.
var annualizedYield = (holdingPeriodYield * (365 / daysToMaturity));
// Display the results
var displayHtml = '
Results:
';
displayHtml += 'Discount Amount: $' + discountAmount.toFixed(2) + ";
displayHtml += 'Holding Period Yield: ' + (holdingPeriodYield * 100).toFixed(4) + '%';
displayHtml += '
Annualized Yield (Approximate): ' + annualizedYield.toFixed(4) + '%';
displayHtml += '
Note: This is an approximate annualized yield. The actual yield may vary slightly due to compounding and specific day count conventions.';
resultDiv.innerHTML = displayHtml;
}
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