In West Africa, the Value Added Tax (VAT) policy consists of a uniform tax rate, but several items consumed by rich and poor households, are exempted. We provide an optimal tax framework to reflect on the welfare effects of such a tariff structure, in the context of current debates on domestic...

This paper employs a production frontier approach that allows distinguishing technological progress from efficiency development. Data on 35 African countries in 1970-2007 show that efficiency losses have constrained growth in Africa while technology progress has played a marginal growth...