This article explains how you can track your marketing expenses. In order to do this you do have to enter supplier invoices for those marketing expenses - if you are using Actionstep in-built accounting then you will be doing this already and there is only a couple of additional steps required. If you use an accounting integration then it is up to whether you double enter those supplier invoices into Actionstep or you obtain your marketing expenses from your accounting package to compare with the income from this report.
Create a supplier invoice by following these instructions here: Broken Link Article or watching the video below.
Make sure to enter a related matter which is the Matter ID of the marketing activity your supplier invoice is in relation to for example, the supplier invoice below is in relation to facebook which has a matter ID of 218.
Enter the cost as indicated by your invoice (please note that you do not need to bill this on to the matter so leave this unticked).
Click save and close.
You will then notice that this expense will appear in the marketing campaign next to the corresponding marketing activity.