Count enumlist occurrences

My problem:
A teacher asks the students to evaluate a project. So there is a parent table (the evaluation request) with project name, date, class. And a child row (the to-do evaluation for each student in the class) with several enumlist columns for success and failure reasons. I want to count how often in the class each success and failure reason is chosen. Example: class is 25 students. Succesreason S1 occurs 20 times, S2 occurs 18 times, S3 4 times, etc.
Is this possible by using virtual colum(s) in the patentable?

It is, but it’s cumbersome. For instance, for S1:

COUNT(
  FILTER("Child Table", ("S1" = [Column 1]))
  + FILTER("Child Table", ("S1" = [Column 2]))
  ...
  + FILTER("Child Table", ("S1" = [Column N]))
)