They started from the assumption that a rational individual maximizes his or her utility or satisfaction as a function of consumption (C) and leisure (L), subject to time and budget restrictions, and they used the criterion of satisfaction with life to evaluate the effects of substitution between leisure time (L) and income (I). The time poverty' threshold was set at 60% of median free time (the sum of time devoted to social life, sport, hobbies and culture consumption). Then the multidimensional poverty threshold was set at the utility point where the time and income thresholds meet and, lastly, individuals were classified in different poverty regimes (see diagram 1.1). These authors propose that people spend more time than is strictly necessary on paid and unpaid work and much of the time pressure they perceive is discretionary .