A tip you might want to also consider: include a filter in the report to weed out any users who have been unenrolled. The filter is 'Is enrolled'
Whenever you enrol a user into a course it automatically creates a completion record. The course completion report source will provide all users that have a completion record for that course.
So when you run the report the numbers you see will include both enrolled users and people who are no longer enrolled.
If you use the filter it will provide the numbers for the enrolled users.
However I don't know without testing whether the filter will filter out suspended enrolments.
(Enrolments can be suspended via Participants > Edit enrolment (gear icon) > Status: Suspended OR via Course > Users > Enrolled users, select users, and under "With selected users..." choose "Edit user enrolments" to change status to Suspended.)