Nigeria's bureau of statistics has overhauled the way it calculates the country's GDP figures. With GDP now estimated at around $510 billion, it has surpassed South Africa as the continent's largest economy. But just because it has earned this accolade – does that make it one of the richest? Plus was the President of the World Bank, Jim Yong Kim, right to say recently that Nigeria is one of just five countries that together are home to two-thirds of the world’s extreme poor? We sift through the statistics to find out if economic development is benefitting everyone in Nigeria. This programme was first broadcast on the BBC World Service.