To be able to use the Cornell PRO-DAIRY, Dairy Water Use Calculator, macros must be enabled. Macros are additional programming code beyond what you traditionally see if you just use formulas in worksheets in Excel. They provide the ability to perform tasks that are more complex, and that may not be available within Excel itself. Among other tasks the PRO-DAIRY calculator opens and completes the DEC water use reporting form which is an adobe pdf file. File operations such as this require the use of macros.