1. Department of Economics, New York University, 269 Mercer Street, New York, NY 10003, and NBER.
2. Department of Economics, University of Minnesota, 1035 Heller Hall, 271 19th Avenue South, Minneapolis, MN 55455, Federal Reserve Bank of Minneapolis, and NBER.
3. CREST-INSEE, 15 Bd. Gabriel Peri, Malakoff 92245, France CEPR, and IZA.