Remittances from Africans abroad are booming, growing fourfold in the past 20 years and shrugging off the global financial crisis, to total $40 billion a year. 'Tapping into this money with so-called diaspora bonds could help provide Africa with the equipment and services it needs for long-term growth and poverty reduction,' World Bank policymakers Ngozi Okonjo-Iweala and Dilip Ratha wrote in an op-ed in the New York Times.