Vivien narcisse Wabo nokam Research Centre for Economics and Management (CREM, 6211 UMR, CNRS) University of Yaounde II   Rue Ngousso Yaounde, Center no Cameroun   wabonokam@gmail.com             JEL Areas: C1 : Econometric and Statistical Methods: General H5 : National Government Expenditures and Related Policies National Government Expenditures and Related Policies: General