for helpful comments. Finally, we thank the audience at the ASSA meeting in New Orleans, the Bernoulli Center for Economics in Basel, the Cleveland FED, the European Workshop on Monetary Theory in Paris, the Symposium on Money and Banking in Strasbourg, the Southern Workshop in Macroeconomics in Auckland and the universities of Paris and Waikato. The opinions expressed here are those of the authors and shall not be interpreted necessarily as those of the Banque de France, the Eurosystem or the OECD. All remaining errors are our own.† Banque de France, Pomone -Monetary policy studies division 41-1422, 31 rue Croix des Petits-Champs,