Real shocks and real exchange rates in really long-term data

There is little consensus concerning the sources of fluctuations in real exchange rates. In this paper I assess the nature of the shocks that drive the real U.S. dollar-U.K. pound exchange rate, analyzing 130 years of data. I first show that wars, which are examples of a (transitory) real shock, are significant. I next use an alternative empirical approach, in which I identify various types of real and nominal shocks. I find that output shocks and monetary shocks account for approximately the same percentage of the variance of the real exchange rate over short horizons. The monetary shock is decomposed into monetary base and money multiplier shocks and the output shock is decomposed into supply and demand shocks. Essentially all of the effect of the combined output shock is due to the demand shock. The effect of the monetary shock is accounted for by both money multiplier shocks and monetary base shocks in roughly equal amounts. Thus, the paper suggests that the contributions of real and monetary shocks are roughly equal overall, while shedding light on the nature of those shocks.