On the heterogeneity in longevity among socioeconomic groups: scope, trends, and implications for earnings-related pension schemes / Mercedes Ayuso (University of Barcelona), Jorge Miguel Bravo (NOVA IMS, Université Paris-Dauphine and ORBio, Portuguese Insurers Association), Robert Holzmann (University of Malaya, University of New South Wales, IZA, CESifo and Austrian Academy of Science) ; IZA. Bonn : IZA, July 2016