An addin program for Microsoft Excel version 7.0 or higher (Excel for Windows 95, Excel 97 and Excel 2000). This addin includes the following functions: Adjusted Black Scholes valuation of Call and Put options. Calculation of Interest Expense based on average debt outstanding without 'Circular Reasoning' when the ending debt outstanding depends on current period interest expense. The calculation includes tax consideration based on any of several available methods. Calculation of Interest Earned without circular reasoning. Days Sales Outstanding for receivables based on successive comparison of historic period sales. Debt Equity calculation with results in XX:YY form. Compound Interest calculation based on the compounding of component rates.