We derive a theoretical balance of payments current account model from a framework that assumes a monetary model of exchange rates as a first state of the world, but then presumes the existence of deviations from purchasing power parity. In such a model there is slow price adjustment where short-run exchange rates deviate from long-run equilibrium exchange rates. Under these conditions there are accumulations of net foreign assets due to current account imbalances. A nonlinear model results where there is dependence between exchange rate deviations from equilibrium and the current account, as well as a concurrent dependence of the current account on exchange rate deviations. Furthermore, the current account is also shown to depend on the demand for money. Thus the theoretical explanation of the current account is concomitant on the short-run exchange rate and the determinants of money demand.Keywords: Current account, Net foreign assets, Exchange rate deviation, Nonlinear monetary model, Money demand JEL Classification: E41; F31; F32.
Current Account AnalysisCurrent account analysis has progressed from the elasticities and absorption approaches to the Mundell-Fleming framework, then to the Monetary, Intertemporal and Portfolio approaches. Our brief summary below will discuss the monetary model last, since it is used as a platform on which we build our own model. Current account models can be said to have begun with the trade analytics of elasticities and absorption approaches, followed by the expanded scope of the Mundell-Fleming model which included international capital flows and allowed monetary and fiscal policy analysis. Improving on both the short-term horizon and depth of the Mundell-Fleming model, the intertemporal approach assumes that the behavior of the current account reflects the intertemporal choices of economic agents. Basically the current account depends on intertemporal consumption which determines savings, and on the world-wide equality of the marginal product of capital which determines investment.