Asymmetric price rigidity and the optimal interest rate defense of the exchange rate: Some evidence for the US

This paper analyses the optimal monetary policy under incomplete exchange rate pass-through and asymmetric price rigidity. In a general equilibrium sticky price model of an open economy we find that the optimal interest rate rule is to respond to all types of shocks in an economy: real exchange rate shocks, supply shocks and demand shocks. We concentrate our analysis on the interest rate defense of the currency. We claim that the extent of the optimal response of the interest rate to exchange rate shocks depends positively on the degree of pass-through and negatively on price rigidity. Therefore, in the presence of asymmetric price rigidity, the optimal monetary policy should be non-linear, and the interest rate should be adjusted more in case of depreciation of the domestic currency than in case of its appreciation by the same magnitude due to higher downward price rigidity and lower downward pass-through, which are observed empirically. We test this prediction for the US economy and find that the US monetary policy is asymmetric indeed with higher reaction of the interest rate to depreciations of US dollar than to appreciations of the same size.