Comparing Data in a Straight table

[#1]

Hi All,

I am very new to Qlikview so please point me in the right direction. I have a straight table:

Dimentions:

Code, Description,InvNumber,DeliveryNote

Expressions:

Items = Sum(Sales Order Qty) - Sum(Credit Note Qty)

Will it be possible to only subtract the credit note qty if the InvNumber = DeliveryNote in the selection, else ignore credit note qty. I've attached a print screen.

Thanks,

[#2]

Hi Miguel,

Could you please give me the syntax for 8.5?

Thanks,