The first thing that you need to do when creating your own Custom Report is to select the different widgets that you would like displayed. As you might already know, you can add the widgets that suit you best by choosing from the different widget categories available and then explore their amazing potential.
In the Lead Generation Category, one of the widgets included is named "Performance chart". This widget provides you with a summary of the most important statistics regarding your landing pages, such as the total visits, clicks and subscriptions. Note that said widget can not be filtered by other criteria.
1. Select the Performance chart widget by clicking on the Add button and then tap on Save. 
Please keep in mind that there are several filters to choose from that can be applied to the corresponding widgets. Furthermore, you can always export the data of each widget in order to have them at your disposal at all times.