The average number of passengers per car on long journeys is 2.25. (See https://www.statistiques.developpement-durable.gouv.fr/se-deplacer-en-voiture-seul-plusieurs-ou-en-covoiturage-0).
This figure is used to calculate the cost-effectiveness of holiday journeys (rather than the number of people in the household).
To find out more about this rule in our model, run the calculation by clicking on the button below.
