Youssouf Kiendrebeogo CERDI, University of Auvergne   65 Boulevard François Mitterrand BP 320 Clermont-Ferrand, 63009 France   youssouf.kiendrebeogo@udamail.fr   http://cerdi.org/           JEL Areas: F4 : Macroeconomic Aspects of International Trade and Finance: General E4 : Money and Interest Rates: General