You can check how many documents have been processed via ApprovalMax Capture by looking at the usage breakdown for the current or a previous billing period.
Go to Billings & Subscriptions, open the Subscriptions tab and under Add-on details > ApprovalMax Capture, click on (#) of (#) documents package used:
In the Usage breakdown pop-up, you will see how many documents have been processed in the corresponding billing period:
You can also view usage from different billing periods by clicking on the arrows on either side of the billing period.