Portuguese language in Africa as a second language, in countries like Angola and Mozambique, where Portuguese is an official language, but also in countries like South Africa and Senegal, thanks to migrants coming from Portuguese speaking countries. Some statistics claim that there are over 30 million Portuguese speakers in the continent. Like French and English, Portuguese has become a post-colonial language in Africa and one of the working languages of the African Union (AU) and the Southern African Development Community (SADC). Portuguese co-exists in Guinea-Bissau, Cape Verde, and São Tomé and Principe with Portuguese-based creoles (Upper Guinea and Gulf of Guinea Creoles), and in
West Africa various ethnic groups. For historical reasons, Western European languages such as French, English and Portuguese predominate in Southern and Coastal subregions, whilst Arabic spreads inland northwards. The Economic Community of West African States (ECOWAS), founded by the 1975 Treaty of Lagos, is an organization of West African states which aims to promote the region's economy. The West African Monetary Union (or UEMOA from its name in French, "Union économique et monétaire ouest-africaine") is limited to the eight, mostly Francophone countries that employ the CFA franc as their common currency. The Liptako-Gourma Authority of Mali, Niger, and Burkina Faso seeks to