I am not very clear with the question by i think LOOKUP function should do for you.
I think you want to compare different quarters with respect to different Products in terms of Sales
For example first product 1.7 Cubi...
Sales at Q01 is 208
Sales @ Q-02 is 333
So the difference is 333- 208=125 (which you can see below as well )
So , this is what I did
Please find the twbx file as well.
Please mark the answer as HELPFUL/CORRECT if it has really helped you so that it can help others as well .