Where to define material is a circulating material in joint production? It is mentioned in SAP library for joint production as below
You can specify whether the cost of a circulating material should be included in the material list. The system selects a price for the circulating material from the costing view of the material master record.
If the circulating material is flagged as relevant to costing, the material costs appear in the itemization twice: once with a plus sign and once with a minus sign. The balance is the material input costs.
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