Returns a specified number of items from the topmost members of a specified set, optionally ordering the set first.
TopCount(«Set», «Count»[, «Numeric Expression»])
This function sorts a set according to the value of «Numeric Expression» and returns the top «Count» members, where «Count» is a numeric expression.
Important Like the BottomCount function, this function always breaks the hierarchy.
Topcount(Geography.Cities.Members, 5, Sales)