In your Overview Dashboard menu, the Performance Over Time chart allows you to see the variation of customers perceptions and how they score against your Rating quantity, Response Rate and Transaction Share 

You can select different measures and views from the pick-lists available to view your rating scores from various perspectives.

In the example below, we have selected to measure ratings for service scores and have added in weekends on the chart so we can easily identify any differences which may occur in those scores between week days and weekends.