Banks, markets, and efficiency

A competitive financial system can help reduce banks’ monopoly power and the associated inefficiencies. However, according to Diamond (J Polit Econ 105: 928–956, 1997) and Fecht (J Eur Econ Assoc 6(2), 2004) competition with the financial sector may also constrain the amount of liquidity insurance that banks can provide to households affected by unobservable idiosyncratic liquidity shocks. To study this trade-off, we model competition between banks and between banks and financial markets. Our analysis shows that competition between banks and financial markets can constrain the risk-sharing offered by deposit contracts. This effect is the same if competition between banks mainly affects the reallocation of deposits. However, if banking competition primarily affects new deposits, then such competition only limits inefficient monopoly rents without restraining risk-sharing. We would like to thank Diemo Dietrich, Phil Dybvig, Hans Peter Grüner, Martin Hellwig, Elu von Thadden, Uwe Vollmer, Wolf Wagner as well as seminar participants at the Bundesbank, at the University of Mannheim, at the University of Tilburg, at the 3rd Workshop on Monetary and Financial Economics in Halle, at the University of Lausanne, at the First ProBanker Symposium in Maastricht, at the Global Finance Conference 2005 in Dublin, at the European Economic Association Meeting 2005 in Amsterdam, at the International Finance Conference 2005 in Copenhagen, and at the German Economic Association Meeting 2005 in Bonn. We thank Mike Demott for editorial assistance. The views expressed here are those of the authors and not necessarily those of the Deutsche Bundesbank, the Federal Reserve Bank of New York, or the Federal Reserve System.