Formulas are user-defined equations for calculating the value of a property. You can use a formula to add data about a selected group of objects or object styles to a schedule table after you define the formula property set definition. and then add the formula property definition to a property set definition.
The worksheet you use to specify the formula also lets you evaluate sample results. Formulas can contain variables, operators, and functions allowed in VBScript. For more detailed information about VBScript, go to http://msdn.microsoft.com and search for “VBScript Language Reference.” Additionally, in the Formula Property Definition worksheet, links to online Help are available from the Insert VBScript code and Formula context menus for VBScript items used in the formula.