A random sample was chosen among frequent public transport users with a personalized travel card. Initially, eight hundred (800) users were chosen as treatment in two arms: four hundred (400) with a subsidy equivalent to 40 trips (COP$28,000), and another four hundred (400) with a subsidy equivalent to 30 trips (COP$21,000) per month, for three months. A control group of eight hundred (800) users, who were not offered a subsidy, was chosen as a control. A baseline survey was conducted at the enrollment visit. An exit survey was conducted at the end of the intervention. Weekly, every participant is asked about their use of time and expenses on transport, housing, food, health, and leisure activities. Data on travel card use are not accessible to the researchers until the end of the intervention.