I'm a high school tech integration coach asking this question on behalf of another teacher. He administered a survey to each of his classes, and for one class only, the Question Breakdown is incorrectly showing that all six respondents gave "No Answer":
He knows that this is incorrect because the export file shows each student's response, when they submitted it, etc.:
Any ideas as to why this would happen? His other classes all show the correct question breakdown; they are all using the same survey.
In my experience, this issue happens when the quiz/survey is modified after the students submit. It kind of wipes out the analytics because the version of the quiz and version the students took no longer match.