Knowledge of the influence of depreciation on the costs of machinery usage is required for such decisions as custom hire vs. ownership of machines and timely replacement. Here, the author is developing a technique for estimating the joint effects of the fixed and variable elements on depreciation.

Technological progress in animal production in the last 30 years has been substantial in some ways, negligible in others. On the one hand, livestock production per animal unit of breeding stock has shown gains of the same order as those in crop production per acre of land. But on the other hand,...