1. Jyväskylä University School of Business and Economics, University of Jyväskylä, Jyväskylä, Finland
2. Department of Mathematics and Statistics, University of Jyväskylä, Jyväskylä, Finland
3. The Finnish Centre for Pensions, Helsinki, Finland
4. Finnish Institute for Health and Welfare, Helsinki, Finland
5. Labour Institute for Economic Research, Helsinki, Finland
6. IZA Institute of Labor Economics, Bonn, Germany