Several approaches exist to model the magnitude and composition of the car stock. De Jong et al. (2002) give a review of the recent (since 1995) international literature on car ownership mod‐ elling. In PLANET we will use an aggregate approach. Other examples of this approach can be found in TREMOVE (De Ceuster et al., 2007) and ASTRA (Rothengatter et al., 2000). We first describe the general principles, and then discuss the different steps in more detail. The general approach is similar as in ASTRA and TREMOVE. For each car type the vehicle stock is de‐ scribed by vintage and vehicle type. .
