NBER Working Paper No. 13147
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Based on a speech given at the Federal Reserve Bank of San Francisco's Annual Macro Conference, San Francisco, California, March 23, 2007. The views expressed here are my own and are not necessarily those of the Board of Governors of the Federal Reserve, the Federal Reserve System, or the National Bureau of Economic Research. I want to thank Michael Kiley, Jean-Philippe Laforte, Deborah Lindner, David Reifschneider, John Roberts, and Jeremy Rudd for their extremely helpful comments and assistance on this speech.