countrows in matrix

Hi,

I have a matrix that I am tracking instances of purchases and deductions by suppliers by period.

What I need to do is to identify an variances by period & by supplier.

E.g.  Each Period needs to show  by supplier a 0 (Nil), -1, +1 (or some other variable) to identify if the count of purchases match the count of deductions in the file, and ignore any 0 (nil) values.

A sample of what I am looking to get at is below along with a simplified sample database.

(Note, I don't need the Grand Total)

I am new with DAX, and it seems I have hit my mental block with this one 🙄.