Atef Khelifi Clerse - University of Lille   7 rue Charles Noël Villeneuve-le-roi, N/A = Not Applicable 94290 France   atefkhe@aim.com             JEL Areas: E3 : Prices, Business Fluctuations, and Cycles: General (includes Measurement and Data) F4 : Macroeconomic Aspects of International Trade and Finance: General