Abuja -With the national elections taking place in a day, here are some facts about Nigeria that you might not have known.
ECONOMY: Nigeria overtook South Africa as Africa's largest economy in 2014, after a rebasing calculation almost doubled its GDP to more than $500 billion, and growth of around 6 percent has made it one of the world's fastest growing economies.
-- Oil accounts for more than 90 percent of foreign revenues and about three quarters of government revenues. The decline of crude prices in recent months has hurt the country's finances, causing the naira to fall about 20 percent since June, despite the central bank spending billions of dollars to prop it up.
The government has also had to repeatedly slash capital spending in the 2015 budget at a time when spending on the elections is surging.
-- Farming and manufacturing have been neglected in the 55 years since oil was found. Successive governments have done little to diversify the economy, though Jonathan's agricultural policies, including removing corrupt middle men from fertiliser handouts, are seen as a step in the right direction.
-- The banking sector is growing rapidly and capital markets are deepening, attracting foreign investment, although the currency falls linked to the elections and the declining oil revenues have led many foreign investors to sit it out for now.
-- Inflation is now in single digits, despite the country's dependence on imports, including everything from toothpicks to refined fuel, but the cost of doing business is exorbitant.
OIL: Nigeria produced just under 2 million barrels per day (bpd) in 2014, the U.S. Energy Information Administration says. Much of it used to be exported to the U.S. but, since that country's shale boom, the biggest buyers are in Asia and Europe.
-- Its sweet, light crude is sought-after because it is easy to refine into high-yield end products such as gasoline.
-- It has four refineries with a combined capacity of 385,000 bpd but they have never reached full production because of sabotage and poor maintenance, causing the country to rely on expensive imported fuel for 80 percent of its energy needs.
-- It also has the world's seventh largest gas reserves and has ambitious plans to increase supply to 13 billion cubic feet per day (cfd) by 2015, roughly double current levels. Despite being Africa's top gas producer, it only generates 3-4 hours of electricity a day.
SECURITY: Sunni jihadist group Boko Haram has killed thousands over the last six years and kidnapped hundreds in its attempt to create an Islamic emirate in the northeast, occupying territory around the size of Belgium by the start of this year.
-- An offensive against the militants in the last six weeks by the army - alongside troops from Chad, Cameroon and Niger - pushed the group out of most of the areas it had controlled.
-- Thousands have been killed in localised violence since the end of military rule in 1999, mostly in sectarian clashes in the central "Middle Belt" that often flare up around election time.
-- Violence by militants in the Niger Delta in the south, one of the world's largest wetlands and home to the continent's biggest energy industry, has eased since an amnesty in 2009.
POPULATION: With around 170 million people, Nigeria is Africa's most populous nation, home to more people than Russia. One in five sub-Saharan Africans are Nigerian.
-- It is one of the world's major oil and gas exporters but well over half of its people live on less than $2 a day. Life expectancy at birth is just 48.4 years, on a par with much poorer West African nations such as Sierra Leone and Chad.
RELIGION: Roughly divided into a Muslim north and Christian south, with sizeable minorities in both. The Muslim community, accounting for approximately half the population, is the largest in sub-Saharan Africa. Traditional beliefs are widespread and many combine them with Islam or Christianity.
-- Home to more than 250 ethnic groups, the three biggest being the Hausa, Yoruba and Ibo. English is the official language but in many rural areas only local languages - of which there are around 520 - are used.