How to calculate treasury bill yield

Introduction:
Treasury bills (T-bills) are short-term government debt securities issued by the U.S. Department of the Treasury. They are a popular investment choice due to their low-risk profile, liquidity, and returns based on the difference between their purchase price and face (par) value. Calculating the yield of a T-bill can help investors understand their returns and make informed decisions related to these investments.
In this article, we will discuss how to calculate the yield of a treasury bill using two methods: the discount yield method and the investment yield method.
1.The Discount Yield Method:
The discount yield method calculates the annualized yield, based on the T-bill’s discount from its face value, divided by the face value itself. The formula for this calculation is as follows:
Discount Yield = [(Face Value – Purchase Price) / Face Value] x (360/N) x 100%
where:
– Face Value refers to the T-bill’s maturity value or par value.
– Purchase Price denotes the price paid for one unit of T-Bill.
– N represents the number of days until maturity.
– 360 is a constant representing days in a year (assuming 30 days per month).
For example, consider a 90-day $10,000 T-bill purchased at $9,800. Based on these values, we can calculate its discount yield as follows:
Discount Yield = [($10,000 – $9,800) / $10,000] x (360/90) x 100% = 8%
2.The Investment Yield Method:
The investment yield method calculates annualized returns based on an investor’s rate of return rather than focusing on the discount from its face value. In this calculation, use the following formula:
Investment Yield = [(Face Value / Purchase Price)^(365/N)] – 1 x 100%
For the same example, we can calculate the investment yield as follows:
Investment Yield = [($10,000 / $9,800)^(365/90)] – 1 x 100% ≈ 8.21%
Comparing both methods, we can see that the investment yield of this T-bill is slightly higher (8.21%) than its discount yield (8%).
Conclusion:
Understanding how to calculate treasury bill yields is important when managing a varied investment portfolio. The two approaches – discount yield and investment yield – help investors analyze their potential returns from investing in T-bills before making decisions on investing or reinvesting in these low-risk securities. Ultimately, determining the right calculation method depends on individual preferences and investment goals.