Mahamat ibrahim Ahmat tidjani LAEREAG, Université de Ndjamena   Goudji, Rue 10050, P31- NDjamena/ Chad Ndjamena, Ndjamena 235 Tchad   ahmattidjanim@gmail.com             JEL Areas: G2 : Financial Institutions and Services: General J2 : Demand and Suppply of Labor: General