The All Enrollments column is looking at all enrollments that began in the previous Month.
The Completed column is looking at Enrollments completed in the previous month.
The Completion % column is looking at the number of enrollment that began in the previous month and have completed the activity.
This is working as expected. If you want the Completed column to only include Enrollments that began in the previous month then you can add the filter All Completed Enrollments (Cohort) = True
