Célestin Koffi Ewool Virtual University of Côte d'Ivoire   ewoolcelestin@gmail.com Abidjan, Abidjan 225 Côte d'Ivoire   ewoolcelestin@gmail.com             JEL Areas: H2 : Taxation, Subsidies, and Revenue: General L2 : Firm Objectives, Organization, and Behavior: General