In this paper we study the drivers of change in individuals' discount rates. Our panel dataset allows us to jointly consider socio-demographics, financial status and literacy, as well as job characteristics among the possible determinants. Our results suggest that individual time-preferences are not stable over time, especially among individuals who hold debts. Labour market variables do not play any direct role. A large part of the variation, however, is not explained by none these drivers. This supports the view that discount rates are related to an underlying unobservable individual trait.