Research suggests that although happiness has a strong genetic component, about 50% of the differences between people in their life happiness can be attributed to external factors (Weiss et al. 2008). While psychologists have long been interested in the external factors that correlate with subjective well-being, only relatively recently has this topic captured the attention of economists. It is perhaps not surprising that a major emphasis in economics studies is on the links between income and subjective well-being (for example, Clark and Lelkes 2005; Dehejia et al. 2007; Easterlin 1995; Layard 2005).