Describe the bug

179 students took an exam, and the exams were uploaded to a bulk upload electronic gradeable.
These were all manually graded.
1 student took a makeup exam, which was graded offline and entered as a grade override.
(There was no submission for this makeup student).

The interface is confusing:

Also, the button on the main gradeables page is red, because the grading completed percentage does not equal 100%

Sometimes we will use grade override to give a different score for a student who had a submission.
Sometimes we will use grade override to give a score to a student who had no submission.

The statistics should make sense in both cases.

The percent completed should never be > 100%.
And if the percent completed is 100%, all students with a submission should have a fully graded assignment & a score.

We should probably list the count of overrides on the statistics page, probably right next to the count of unresolved grade inquiries. We should probably separately list overrides of students with and without submissions.

NOTE: We have some options to configure the grading statistics / percent complete / etc:
Make sure we test with each option and they are working correctly.