a.k.a Reversal Cost Method
Similar to technique in 1D.
Reduces the manufacturing cost of the main product, not by the actual revenue received, but by an estimate of the by-product's value at the time of recovery.
The by-product is charged with this estimated amount, and the production cost of the main product is credited.
Any additional costs of materials, labor, or factory overhead incurred after split-off are charged to the by-product.