Only selected rows in matrix without filtering total

I have a table like below. I want to create a matrix that shows only certain subcategories and segments, because there are way to many. I want to the matrix to also show the total category value.

Matrix should look like this:

Category - 820

   Subcategory A - 420

       Segment 2 - 200

So basically, I just want to 'hide' certain rows. I can't do it using filters, because then the total category does not add up. I also tried with excluding rows in the matrix, but that also affects the highest level. Is there a way to do it?