Mick Silver is Principal Statistical Methodologist, Real Sector Division, Statistics Department, International Monetary Fund. Previously he was Professor of Economic Statistics, Cardiff University, and ASA/NSF Senior Research Fellow, US Bureau of Labor Statistics. He has contributed as chapter author and, in one instance editor, of international Manuals on price index measurement and the System of National Accounts. Publications include the Journal of Political Economy, Journal of Econometrics, Journal of Business and Economic Statistics, Economic Journal, IMF Staff Papers and chapters in NBER books.