Why young, urban or rich Africans are less likely to vote

PURVEYORS OF BALLOT papers, indelible ink and polling booths will do well in Africa this year. No fewer than 18 countries are to hold general elections. Not all will be free and fair, but in many the stakes are high. In Ethiopia the popularity of Abiy Ahmed, a reformist prime minister, will be tested at the polls for the first time. Burkina Faso, which is battling jihadists, will hold only its second poll since Blaise Compaoré, a long-serving dictator, was overthrown in 2014. And in Ghana President Nana Akufo-Addo faces a tight race for a second term.