Rank by Brand by Product

Hello,

I need some assistance in ranking some data using multiple criteria. I have attached a sample. What I need to do is to rank the Product within each Brand based on their Sales. So for example under the "A" Brand I need to rank each Product based on sales volume, then under the "B" Brand I will need to do the same thing and so on and so forth. I need to basically populate column D on the attached automatically. I've searched around and found the SUMPRODUCT method, but it only works using one criteria. Any help would be appreciated.

Thanks!