Adam,Since the Date2Num function takes string as argument you need to convert the date value of the field to string. This can be done using the Format function as below: NumericField102 = (Date2Num(Format("MM/DD/YY", AvailEndDate), "MM/DD/YY") - Date2Num(Format("MM/DD/YY", AvailStartDate), "MM/DD/YY...