Every customer is unique to us!
In the Workflow Summary Dashboard, you can find a widget for Sum of Unique Customers. It will show you a sum of all customers the agents were interacting with within the time frame.
Careful with the counting though!
One customer can interact with you across multiple channels within the given time frame. That means that you will see one unique customer for FB and one for TW when the same customer contacts you on each of the platforms. (=2)
However, if you filter both FB and TW in the reporting channels, there will be only 1 unique customer ;)
In March we had 106 unique customers contacting us. 100 on channel A and 8 on channel B. Those numbers do not add up, right? This means that there were 2 customers who wrote us on both channel A and B :)