Is there a way to make the "Range" within a formula only use cells with certain data in

So I have a table with customers and their sales by product.
I want to use RANK.EQ to rank each customers sales by which products had the highest sales value.
I want to do this while keeping all customers in the same table but the rank only takes into account the products under their customer number.

I believe RANK.EQ would work, IF there is a way to make the "Range" selective, so have the Range be the customer number column, but have it only look at customers with the same customer number as the row it is currently looking at.

Is there a way to achieve this?

Thanks