On your Dashboard, one of the first options on the left-hand menu is Sales. Once you're on the sales reporting screen, click on the dropdown for the dates you want reported on, and there will be a button that says "Last Year".

Once the screen refreshes to display last year's data, click on the dropdown on the right that says Export, and pick "summary csv" (or another format, if you want). This will download a spreadsheet that shows the total fees paid, amongst other things.