Money Markets, Collateral and Monetary Policy

During the financial and sovereign debt crises, euro area interbank money markets underwent dramatic changes: the share of unsecured borrowing declined throughout the euro area, while private market haircuts on sovereign bonds and bank borrowing from the European Central Bank increased in the South. We construct a quantitative general equilibrium model to evaluate the macroeconomic impact of these developments and the associated policy response. Our model features heterogeneous banks and sovereign bonds, secured and unsecured money markets, and a central bank. We compare a benchmark policy—the central bank providing collateralized lending to banks at haircuts lower than the market—to an alternative policy that maintains a constant central bank balance sheet. We show that the fall in output, investment, and capital would have been twice as high under the alternative policy. More generally, the model allows the analysis of monetary policy tools beyond interest rate policies and quantitative easing.