165
Underlying accounting theory
The asset recognition concept argues for recording by-product inventory in the period of production at an amount approximating its production cost, provided there is a market for by-product. The matching concept requires expensing inventory in the period in which its sale is recorded. These concepts, balanced against the materiality concept, should be considered in selecting the by-product costing method whichever method is chosen, it should be applied consistently from period to period
8-3
Methods of allocating joint production cost to joint products
Joint production cost 9incurred before split-off), can be allocated to joint products under one of the following methods.
1. The market value method, based on the relative market values of the individual products.
2. The average unit cost method.
3. The weighted-average method, based on predetermined weighting factors.
4. The quantitative unit method, based on some physical measurement unit such as weight, linear measure, or volume.
Market value method
Proponents of the market value method often argue that the market value of any product is to some extent a manifestation of the cost incurred in its because more cost was expended to produce it. In other words, were it not for such a cost, a sales value would not exist. Yet, by definition, the effort required to produce each of the joint products cannot be determined. If it could be determined, the allocation could be made on the basis of the relative amount of effort expended on each of the joint products. Furthermore, according to economic theory, prices in a competitive market economy are determined on the basis of the relative scarcity of goods demanded by consumers, not on the basis of the basis of the relative cost of producing those goods.
another argument for using the market value method of allocating joint costs is that it is neutral. That is, it does not affect the relative profitability of the various joint products are not distorted by arbitrary cost allocations. If estimates of market value and additional processing costs are accurate, the market value method will result in each of the joint products showing the same gross profit rate per dollar of sales.
The choice among accounting methods tends to be arbitrary when the proportions of the joint products composing the output mix cannot be changed. However, the choice is not arbitrary if the proportions can be varied and there is relationship between the total joint cost and the total value of the output. This implies especially strong rational support for the market or sales value method if, for given inputs to the joint manufacturing process, two conditions hold; 1 the physical mix of output can be altered by incurring more (or less) total joint cost relative to other production costs and (2) this alteration more (or less) total market value.