Revenue is one of the most important metrics used to measure the success of a marketing campaign. If you navigate to the Metrics tab of your account and select Placed Order, you will see a graph of the number of orders placed over an adjustable time period. Here, you can toggle the view from Total to Value to view revenue associated with these orders.
Once you toggle to Value, the metric title will change to Revenue.
Using the Advanced Filters option, it is possible to dig further into this data and see precisely what this revenue can be attributed to. For example, you might be interested in seeing which signup source has given you the best leads. To do this, filter the graph by $source, and you will see the revenue associated with each signup method you implement.