This time of the year, while you are collecting information for the accountant, and you are in that frame of mind. It would be a good idea to check your sales security indicators. This is a good check and if something is wrong, you may find it there.
What these indicators do is gives you a detailed breakdown for each operator on no sale, voids, count, totals, refunds, negative items and discounts. In my experience, unusual no sale and voids for each operator are the most important of these indicators.
Go to cash register reports
Open Staff and click on "Sales security indicators"
Select required period, in this case the last twelve months.
See how you go.
The report comes out in excel so you can edit it.