How does the potency of fiscal policy depend on a country's exchange-rate regime? The Mundell-Fleming theoretical model predicts that fiscal policy can affect output under both fixed and flexible exchange rates, but that the effect is larger when the exchange rate is fixed. Using a panel data set of 61 countries for the 1951-2007 period, the paper shows that fiscal policy is indeed more potent under fixed exchange rates than under flexible, and that the difference is substantial: the estimated models imply that maintaining a fixed exchange rate raises the long-run fiscal multiplier by roughly a third.

JEL Classification E62, F41