Calculating No. of Options Sold (more complicated than it sounds, trust)

[pand23]

Hello, I've tried searching for a solution, but to no avail.

Below is a sales report of some Nike sneakers.

Product is the item down to size level.

Master is the Option Count. For example, a t-shirt, 400280 comes in 3 sizes, S, M and L. Hence why product is 400280-001 (small), 002 (medium) and 003 (large).

However it remains 1 option (not 3).

There are 7 options below with 12 units sold in total.
How would I express a formula within a Pivot Table as a calculated field to show the number or sum of options sold?
I have tried to come up with a solution, but it is too advanced for me.

I know the answer is 4 as there are sales against 4 unique "MASTER" references, but I don't know how to write a formula to express this. Would it be even possible as a calculated field in a Pivot? Thank you

7 12 Brand Product MASTER MASTER2 Option Count Units Sold Options Sold 4 Nike 400281-005 400281 400281 1 Nike 400281-004 400281 Nike 400281-003 400281 2 Nike 400281-002 400281 1 Nike 400281-001 400281 Nike 400280-003 400280 400280 1 Nike 400280-002 400280 Nike 400280-001 400280 5 Nike 400248-001 400248 400248 1 Nike 400247-001 400247 400247 1 Nike 400246-001 400246 400246 1 1 Nike 400245-005 400245 400245 1 Nike 400245-004 400245 Nike 400245-003 400245 1 Nike 400245-002 400245 2 Nike 400245-001 400245 Nike 400244-001 400244 400244 1 <colgroup><col><col><col><col span="7"></colgroup><tbody> </tbody>

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