To only show the students who have an active enrollment as of the day you are running the report, add to your Ad Hoc Report the field:
Student->Demographics->activeToday
and say the value for this field must " = 1" (meaning "yes").
To show only departed students, you could set the same field with the requirement "activeToday = 0" (meaning "no")
Student->Demographics->activeToday
and say the value for this field must " = 1" (meaning "yes").
To show only departed students, you could set the same field with the requirement "activeToday = 0" (meaning "no")