On the Discounts and Cancellations section in the Reports tab you can check out the removed items, discounts, refunds, reprinting and issued-unpaid events in your places, and the total cost of those actions.
If you manage multiple businesses you can choose what data you want to display on the top-left menu (1). You can also set a specific time period (2), you can also export your data from both the chart and the table (3), the export is generated in .xls format for Excel. The charts on the Discounts and cancellations section work like the charts in most other sections in the Reports tab, and you can learn how to work with them on this article.
In the table you see a possible loss, the sum the amount of bills affected and their number. On the chart, you can use the checkboxes (4) to display only the individual actions in this tab.