Exploratory study of long-distance carpooling supply and public financial incentives: The case of France

To meet its reduction targets in the mobility sector, the French government aims to support carpooling as a means to achieve more efficient car use. Recognizing the gap between these targets and current levels, the government introduced a financial incentive of 100€ per new driver in 2023. This paper seeks to provide an exploratory study of long-distance carpooling supply in France, with particular attention to this public policy, while accounting for a broad set of intermodal and intramodal factors. The study relies on an empirical analysis of original data covering the period 2020–2024. The primary findings from the Seasonal-Trend decomposition analysis confirm the impact of COVID-19 restrictions in 2020 and the subsequent rebound in 2022, with a similar trend continuing into 2023. To explore this further, a Multiple Linear Regression model incorporating a large panel of variables was developed. Results indicate that new driver uptake correlates more with other influencing factors than with the subsidy itself. They highlight a strong complementarity with train services, as new drivers are associated with train transport shortages and seasonality, particularly during peak demand periods.