Nigeria has just emerged from a tough recession, but brighter days lie ahead for Africa's economic powerhouse.
Buhari has been away for two months. Is his vice president, Yemi Osinbajo, preparing to succeed him?
Nigeria slipped into recession in 2016 after militants blew up oil facilities. But the government is trying to negotiate peace.
The West African country has been in recession since mid-2016.
Muhammadu Buhari has been out of the country for almost three months in 2017 as Nigeria battles recession and insurgency.
Christian pastor Yemi Osinbajo is Nigeria's acting president while Muhammadu Buhari is on sick leave.
Muhammadu Buhari, 74, has rarely been seen in public since returning from seven weeks of sick leave in March.
Buhari has missed several cabinet meetings and is still recovering following a months-long absence in the U.K.
Buhari returned in March from a two-month medical absence in the U.K.
Nigeria has suffered from falling oil prices and a lack of foreign exchange.
The singer has called for a peaceful march against the country's economic crisis.
Buhari's government has faced an economic crisis and major threats to stability.
It's been a year of political engagement and tomfoolery for African social media users.
The championship-winning team protested outside the National Assembly and the presidential villa.
Nigeria recently lost the title of Africa's biggest economy to South Africa.
Militancy in the Niger Delta has slashed oil production by over 400,000 barrels per day.