Unable to get unique count of field in line chart

I have a table (Product History) that contains a daily history of another table (Products) in my app. I am trying to create a line chart in the Product History table that shows how many Clients in our database subscribe to each product we offer, but I can't seem to figure how how to make this work. The closest I can get to this idea is listing the number of product subscriptions, rather than the number of clients for each product type because a `Client` can have multiple products (ie- Acme, Inc. has a record for SEO and Advertising in the `Product History` table).

Here is my ideal report setup:

X Axis (horizontal): Date

Y Axis (vertical): # of Clients (this is what I can't figure out - this field does not exist yet)

Series: Product Type

The table `Product History` is written to every day by a Pipeline that copies field values from `Products`, so that we have a daily historical record of the `Products` records.

What am I missing here? Thank you in advance 🙏 .

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Matt Makris
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