Exchange market pressure in interest rate rules

Many central banks pursue some kind of exchange rate objective. We derive what variables the central bank should look at when setting the interest rate to implement a given objective. Exchange market pressure (EMP), the tendency of the exchange rate to change, emerges as the key variable. This yields a policy rule for the interest rate where EMP is added to, say, a Taylor rule. The coefficient for EMP depends on two structural parameters, namely the effectiveness of the interest rate to ward off depreciation, and the degree of exchange rate management. The rule can implement many regimes, from floating to intermediate to fixed rates. It can be applied to many models, and we illustrate it in a New Keynesian model for a small open economy.