Yes you can. Applying a custom grading scale to a class displays the ‘Progress so far’ data (average score divided by the number of scorable activities in the class, multiplied by the number they have completed) in teacher and learner data views. If you wish to hide this from learner data views, you can disable the switch below the grading scale on the Class grade settings page (see Class grade settings screen below).
Note that ‘Progress so far’ data is not available in classes using the Cambridge One grading scale.