Linked columns: showing a field from a related table — Only counting some of them

Under Only include where you can narrow which linked records are counted or totalled — “the orders that are posted”, “the deals that are Closed Won”. Add as many conditions as you need; all of them must match. The field you test can live on the linked record itself, or one step further along. The picker lists both: Stage is a field on the order, Company → Tier travels from the order to its company and tests the tier there. That second kind is what lets the thing you're filtering on stay where it belongs — you don't have to copy a country, a type or a tier onto every child record just to make the filter possible. So “the total value of this customer's orders, only the posted ones, and only where the contact is in the US” is one column, not a schema redesign.