Calculate Early Payment Discounts Before Taxes For a Vendor
        To calculate discounts before taxes are applied when paying a   vendor:
        
            - Open the Options tab in the   vendor record. 
How?- In the Home window, click Vendors & Purchases on the navigation pane.
 - In the Tasks pane, right-click  the Vendors icon and select Modify Vendor from the menu.
 - Select a vendor from the list and click OK.
 - Click the Options tab.
 
 
            - Select the Calculate Discounts Before Tax check box.
 
            - Click Save 
 and Close.