1. Center for Economic and Social Research, University of Southern California, 635 Downey Way, Los Angeles, CA 90089, USA
2. Federal Reserve Bank of New York and CEPR, 33 Liberty Street, New York, NY 10045, USA
3. Department of Economics, University College London and CEPR, Gower Street, London, WC1E 6BT, UK
4. Faculty of Philosophy, Radcliffe Humanities, University of Oxford, Woodstock Road, Oxford, OX2 6GG, UK
5. Department of Economic Analysis, University of the Basque Country, Avenida Lehendakari Agirre, 83, Bilbao 48015, Spain