1. Population Research Centre, Faculty of Spatial Sciences, University of Groningen, Landleven 1, 9747 AD Groningen, The Netherlands
2. Centre for Demographic and Ageing Research, Umeå University, Norra Beteendevetarhuset, 4 tr, Umeå Universitet, 901 87 Umeå, Sweden
3. Department of Geography, Umeå University, Social Science Building, Umeå Universitet, 901 87 Umeå, Sweden