It is generally accepted that people prefer to receive reward earlier rather than later. A positive rate of time preference is routinely used in economic models of intertemporal choice, for example OLG-CGE models. Calibrating an OLG-CGE model is challenging because age-profile data is usually not available. For example, researchers typically have no data on consumption by age group. The conventional way to proceed is to impose a constant rate of time preference, which implies smooth age profile for consumption.