Estimating the total travelled mileage and its evolution by type of vehicle is a cornerstone of mobility patterns’ understanding at national level.
In France, it’s possible to estimate road transport demand by using two different methods:
- by using annual statistics selected from the National Travel Surveys (Comptes Transports de la Nation or CNT) or
- by using models like KILOM, developed by INRETS within this project.
The modelling procedure of KILOM aims to provide a monthly estimation of the road transport demand i.e. the total mileage on any type of road networks and all types of road engines. This monthly perspective allows to size and to figure out the variability of road transport demand.
The modelling process estimates the total mileage on any road by crossing the total numbers of vehicles (for any types of vehicles: from cars to lorries) and the total consumption of fuel. This modelling requires assumptions on the fuel consumption by type of vehicles and on life duration of vehicles, estimation of fuel purchases in foreign countries by French households and firms, and most of the time series on car park, fuel price and average fuel consumption.
The conceptual architecture of the model is to put in balance the fuel deliveries and the actual consumption of fuel by the vehicle fleet for each type of road engines, from cars to trucks. The results are aggregated in order to provide the total mileage per road engine.
By mean of the developed Excel tool, it is possible to calculate seasonal factors applied to produce monthly series starting from an input of monthly and annual data. The Excel-run tool is very easy to use. It is only necessary to enter the monthly and annual data 'input' of one year in a table to obtain the monthly mileages.
After exposing the modelling principles of annual mileage, the principles at the basis of seasonal effects modelling are presented:
- the monthly payment model based on fuel leaks at borders based on the ARIMA monthly model of fuel deliveries depending on differences in fuel price in neighbouring countries;
- the monthly payment model of the park based on the registration statistics;
- the monthly mileage payment model (which was not processed);
- the monthly fuel consumption payment model for both categories of vehicles: passenger cars, LDVs, HGVs and coaches.