Hi Sudhir,
You can open these as a Labour Item or Non Invenotry Item code "Bonus X" named "Bonus XX%"
how many max types they have ?? in UDF you can select against each item
Item1 1 1000 Bonus 10
Item2 1 2000 Bonus 10
On header level open 2 UDF "Bonus 10%", "Bonus 5"
sum the line total of those whose row UDF is "Bonus 10" and so on for header Bonus 5
the reason to make the calculation on header is because you cannot do the calc of rows into rows
so you need to take the values to header do the calc. and bring back from header.
Feel free for any unclear things