Matthew Kotchen is professor of economics at Yale University and a research associate of the National Bureau of Economic Research. James H. Stock is the Harold Hitchings Burbank Professor of Political Economy at Harvard University, a faculty member of the Harvard Kennedy School, and a research associate of the National Bureau of Economic Research. Catherine Wolfram is the Cora Jane Flood Professor of Business Administration at the Haas School of Business, University of California, Berkeley, and a research associate of the National Bureau of Economic Research.