Capacity utilization and depreciation-in-use

In this paper, the effect capacity utilization has on the depreciation of capital goods is studied, starting from a quadratic approximation to a normalized short-run cost function. Expressions for the optimal rate of capacity utilization, the demands for labour and energy, and for investment are obtained. Investment is a function of past capital stock, expected future capital stock, expected future relative prices and expected future depreciation rates. Expectations are modelled via instruments. The model is tested using US total manufacturing quarterly data. Depreciation dependent upon usage is found to be both statistically and economically significant.