YIELDMAT Function (Gnumeric)
Calculate the annual yield of interest-at-maturity securities in Gnumeric with YIELDMAT, dated cash flows, optional day-count basis and price checks.
Verification status: Gnumeric 1.12.57 bounded ssconvert tests; source-version differences explicitly scoped; no GUI. How formula examples are checked
YIELDMAT calculates an annualized yield for a security whose interest is paid at maturity. It accounts for interest accumulated from issue through settlement and from issue through maturity. It is not the periodic-coupon YIELD calculation and does not describe a general portfolio return.
Syntax and inputs
=YIELDMAT(settlement,maturity,issue,rate,price[,basis])
The first five arguments are required. Settlement is the purchase/settlement date, maturity is the redemption date, and issue is the original issue date. Use actual spreadsheet dates, normally supplied with DATE. Rate is the nominal annual interest fraction, such as 0.06 for 6%. Price is quoted per 100 face value; numeric 98 means 98 per 100, not 98% of a separate currency amount supplied elsewhere.
Optional basis defaults to 0, US 30/360. Other supported bases are 1 actual/actual, 2 actual/360, 3 actual/365 and 4 European 30/360. These choices affect the year fractions, especially around unequal months, leap years and irregular date intervals.
Use economically valid ordering issue ≤ settlement < maturity, nonnegative rate and positive price. The inspected callback validates dates, basis and negative rate but does not comprehensively enforce every economic relationship. A numeric result is not proof of sensible inputs.
Worked example
=YIELDMAT(DATE(2024,7,1),DATE(2025,1,1),DATE(2024,1,1),0.06,98,0)
The expected yield is approximately 0.099009900990, or 9.900990099%. Omitting the final basis argument gives the same result for this example.
Independently, the issue-to-maturity fraction is 1 year, issue-to-settlement is 0.5 year, and settlement-to-maturity is 0.5 year under basis 0. Maturity proceeds per 100 are 100×(1+0.06×1) = 106. The settlement denominator per 100 includes price plus accrued interest: 98+100×0.06×0.5 = 101. Annualizing the holding-period return gives (106/101-1)/0.5, which is the stated result.
At price 100 with the same dates and rate, the expected result is approximately 0.058252427184, or 5.8252427184%. It is not exactly the nominal 6% because the settlement amount in this convention includes accrued interest.
Advanced application: check the day-fraction calculation
Put issue-to-maturity fraction 1 in A1, issue-to-settlement fraction 0.5 in A2, settlement-to-maturity fraction 0.5 in A3, rate 0.06 in A4 and price 98 in A5. The independent formula =((1+A1*A4)/(A5/100+A2*A4)-1)/A3 reproduces 0.099009900990.
For other dates, calculate the three fractions using the selected basis rather than reusing these convenient halves. Compare quotes using the same basis, interest-payment timing and price convention. A coupon-paid-periodically security requires a different cash-flow model.
Errors and troubleshooting
A negative rate returned #NUM! in the native test. Invalid dates or unsupported basis are rejected by the inspected callback. Settlement equal to maturity makes the annualization interval zero; reject it in your model rather than depending on the resulting error. Reversed dates and inappropriate prices can also produce misleading outputs.
Keep rate, price and result formatting distinct. Rate and yield are fractions that can be percentage-formatted; price is a quotation per 100. Do not multiply an already percentage-formatted result by 100 again. A theoretical yield omits taxes, trading costs and other cash flows unless separately modeled.
Version and portability
Official NEWS lists YIELDMAT among new functions in Gnumeric 1.1.6. These examples were executed in 1.12.57, whose retained financial implementation was inspected. The exact last functioning release is unestablished. Similar names in other spreadsheets do not establish identical date parsing, default basis or invalid-input behavior. Verify an exported workbook in its destination application.
Official sources
Native verification scope
On 17 October 2026, Gnumeric 1.12.57 ssconvert recalculated 4 bounded YIELDMAT fixture records in C.UTF-8. Saved input formulas and output cells were independently read back and matched to the recorded evidence. Recorded results agree with the independent arithmetic or special-function reference calculations to the documented numerical tolerance. This is engine evidence, not a GUI test or screenshot. Derived worksheet checks are mathematical examples unless separately recorded in the fixture. No execution of 1.12.62 or untested extreme inputs is claimed.