Postwar U.S. Business Cycles: An Empirical Investigation

A study documents some features of aggregate economic fluctuations sometimes referred to as business cycles. The investigation uses quarterly data from the postwar US economy. The fluctuations studied are those that are too rapid to be accounted for by slowly changing demographic and technological factors and changes in the stocks of capital that produce secular growth in output per capita. The study proposes a procedure for representing a times series as the sum of a smoothly varying trend component and a cyclical component. The nature of the comovements of the cyclical components of a variety of macroeconomic time series is documented. It is found that these comovements are very different than the corresponding comovements of the slowly varying trend components.