First Author:   Agnes Zabsonre Nazi Boni University Burkina Faso, Research Fellow Partnership for Economic Policy (PEP) Kenya zabagnes@yahoo.fr   01 BP 1091 Bobo-Dioulasso, Burkina Faso   66756762(Phone) 66756762(Fax) Second Author: Maxime Agbo School of Statistics, Planning and Demography, University of Parakou, Benin agbomaxime@gmail.com   Parakou, Benin