Operating Cost for produced items

operating cost is taking for total number of items to be produced in production order.
Is it possible to make it to calculate depending on number of items produced.
Ex: process cost of 1 Item to produce = 10 Rs
Cost of raw material required for 1 item = 50 Rs ( Total raw material cost = 50*100= 5000 Rs)
Production order = 100 items
produced items = 80 items

In Erpnext it takes as total used raw material cost + operating cost for items to be produced i.e. 8050+10010

I want the cost to be calculated as total used raw material cost + operating cost for produced items
8050+8010

Can anyone help me?

@santosh_baburao
You can override it by writing custom script.

Thanks Nick.
Could you please tell me how to do that? I am not aware of programming languages.

Kindly tell me the script code if you know.