Excel 2003 May Yield the Wrong YIELD

One of the Microsoft Excel 2003 financial functions will give you the wrong answer under a particular set of inputs. If you are using the YIELD function, and the security settlement date is the 30th or 31st of the month, the maturity date is the 30th or the 31st of the same month, and the Basis parameter is 4. Microsoft has a hotfix at http://support.microsoft.com/kb/925797, which must be applied on top of some previously released hotfix packages, described on that page.