Accounting for joint production processes
Joint products are two or more products produced simultaneously by the same process up to a split-off point. The split-off point is the point at which the joint products become separate and identifiable. For example, oil and natural gas are joint products. When a company drills for oil, it gets natural gas as well. As a result, the costs of exploration, acquisition of mineral rights, and drilling are incurred to the initial split-off. Such costs are necessary to bring crude oil and natural gas out of the ground, and they are common costs to both products. Of course, some joint products may require processing beyond the split-off point. For example, crude oil can be processed further into aviation fuel, gasoline, kerosene, naphtha, and other petrochemicals. The key point, however, is that the direct materials, direct labor, and overhead costs incurred up to the initial split-off point are joint costs that can be allocated to the final product only in some arbitrary manner. Joint products are so enmeshed that once the decision to produce has been made, management decision has little effect on the output at least to the initial split-off point. Exhibit 7.10 depicts the Joint production process. Exhibit 7.11 depicts the usual production process in which two products are manufactured independently from a common material. For example, a Taurus and a Mustang require steel, but the purchase of steel by Ford Motor Company does not require the manufacture of either model of car.