The Federal Republic of Nigeria covers an area of 923,768 sq. km on the shores of the Gulf of Guinea. It has Benin on its Western side, Niger on the North, Chad to the north-east and Cameroon to the east and south-east. Its November 1991 census stood at 88,514,501 and has risen above 120 million currently. It is the most populated country in Africa. Its population is extremely diverse with well over 250 ethnic groups, some numbering fewer than 10,000 people. Ten ethnic groups including Hausa-Fulani, Yoruba, Ibo, Kanuri, Tiv, Edo, Nupe, Ibibio and Ijaw account for nearly 80% of the total population. Most of its population is concentrated in the southern part of the country, as well as in the area of dense settlement around Kano in the north. Between the two areas is a sparsely populated middle belt.