María-jesús Freire-serén University of Vigo, Spain   Facultad de Ciencias Económicas y Empresariales Campus As Lagoas-Marcosende Vigo, 36310 Spain   mjfreire@uvigo.es             JEL Areas: D9 : Intertemporal Choice and Growth: General E2 : Macroeconomics: Consumption, Saving, Production, Employment, and Investment: General (includes Measurement and Data)