Equipment Investment and Economic Growth*

J. Bradford DeLong, U.C. Berkeley

Abstract

We use disaggregated data from the United Nations International Comparison Project and the Penn World Table to examine the association between different components of investment and economic growth over 1960–85. We find that producers’ machinery and equipment has a very strong association with growth: in our cross section of nations each percent of GDP invested in equipment raises GDP<br />growth rate by 1/3 of a percentage point per year. This is a much stronger association than can be found between any of the other components. We interpret this association as revealing that the marginal product of equipment is about 30 percent per year. The cross nation pattern of equipment prices, quantities, and growth is consistent with the belief that countries with rapid growth have favorable supply conditions for machinery and equipment. The pattern is not consistent with the belief that some third factor both pushes up the rate of growth and increases the demand for machinery and equipment.