As with all forecasts, in estimating road traffic for large periods of time (20 or 30 years) there is uncertainty regarding the outcome of key input variables, such as future GDP growth, fuel prices, and population. The forecasts presented should be read as projected trends for traffic, considering the most likely evolution of the input variables.
The main indicators affecting the evolution of road traffic are: population and employment, Gross Domestic Product, average net wage gain, vehicle fleet and motorization rate, Average Daily Travel, and road capacity and network utilization rate.
To assess the maximum variation around the central forecast, we model scenarios based on a combination of these indicators. The medium scenario - average car park consumption is expected to decrease between 2030 and 2035. The high demand scenario combines a high per capita GDP, an increased motorization rate, moderate population decline, increased employment rate, low oil prices, and high fuel economy. The low demand scenario assumes a low GDP and therefore low per capita income, a sharp decline in population and employment rate, a degradation of road infrastructure quality, high oil prices, and a low level of fuel economy.
It must be emphasized that all forecasts are uncertain. This is the result of the uncertainty of the input indicators. The forecast for the period 2020 – 2050 is more uncertain compared to previous road traffic forecasts. It is unrealistic to take a high growth version of each variable and on this basis make a high forecast because the probability of a high rate continuing for 30 years just because the first year has a high rate is very low.

traffic forecast; evolution of road traffic;