By using Index( ) in calculated filed and drag that calculated field in rows shelf we can achieve this.Please find the attached twbx.I hope this solves your problem


Step1: Create calc field called index ie index( )


Step2: Drag the customer name and calc field index into row shelf.


Right click customer name descending and sort via field [sales]


Step3: create [Top N] parameter with integer data type


Step 4:Create calc field called top10? Title Top 10 calculations – Top10?


if [Index]<=[Top N] THEN "Top N"  ELSE IF [Index]>=SIZE()-[Top N]

THEN  "Bottom n"  else “Others” end end


Drag calculation field Top 10? Into filter then select top n and bottom n.


Drag the new calculation into row.


show parameter control and type 10,20 etc