Need Help in adding another expression to my database

http://s22.postimg.org/wcgll3xkd/image.jpg

[img=http://s8.postimg.org/jgcyn1kv5/image.jpg]

[img=http://s23.postimg.org/lg42y9mtj/image.jpg]

im in need of some serious help....ive provided pics to help with the visualizing and all...

ok as u see in my daily roll call report i have 2 groups..."on program" and "graduates"

these 2 groups are creating in the query...as u see in the 2nd pic... the expression as followed

Expr1: IIf([Date Graduated]<Date(),Date(),[Date Graduated])

next you can see in my 3rd pic the report and the expression that gives the 2 groups there names...it is as followed

=IIf(IsNull([Date Out]),IIf(IsNull([Date Graduated]),"On Program","Graduates"),"Recent Departures")

i will clarify that i took out the names in the roll call but both groups are sorted by the date they came in going down the list


now i need to add another group "Staff Members" to my roll call...what would be best way to do this???

every way i have tried altering the query expression or the report expression result in a blank roll call....thanks and God Bless!!!