On July 13, 2007, Standard&Poor's Ratings Services affirmed its 'B' long-term and 'B' short-term foreign and local currency sovereign credit ratings on Burkina Faso. The outlook is positive. The ratings on Burkina Faso are constrained by a low level of economic development, with GDP per capita among the lowest of rated sovereigns, projected at $520 in 2007; and weak human development indicators. The economy is narrow, with a large informal sector and heavy dependence on cotton cultivation. The ratings are also constrained by the lack of fiscal flexibility, due to the low level of government revenues. These are projected at only 12.8% of GDP in 2007, notably reflecting the narrow tax base. The tight context on the revenue