To see how your discounts are being used, go to the All Reports page from the Reports menu and under the Financial section select "Discount Report". You can also use the Global search and start typing "Discount Report".
You can either type in the code you are interested in reporting on or you can see all of your discount codes by leaving the "Discount Code" box blank. You can also choose to copy and paste the report into Excel for complex sorting and calculation.
Discounted price totals are automatically rolled into the GL and Daily Receipts reports.