The Department for Transport has used the National Transport Model (NTM) to estimate that in 2035 there will be 210 million passenger trips per weekday on average by surface modes (including road and rail, but excluding freight), in Great Britain. Of these, 4.2 million are expected to be over 50 miles long, and 1.5 million trips over 100 miles long.
In addition, the Department for Transport published its most recent air passenger demand forecasts in "UK Air Passenger Demand and CO2 Forecasts" in January 2009, which is available at:
Under a scenario assuming no additional runways in the South East, and using the then latest available GDP projections, this set of forecasts implied that there would be 37.6 million domestic air journeys per year between UK airports in 2030. The Department keeps its aviation forecasts under review and will publish updated forecasts as appropriate.
Growth of trip numbers over the period to 2033 by particular modes, and for particular parts of the network, may differ from these overall figures.
In addition, HS2 Ltd has published a forecast showing it expects there to be 7 million 'long distance' trips daily in 2033. However, this is not comparable to the preceding NTM figures. This is because HS2 Ltd's model of 'long distance' travel is based on a subset of trips which differs from the national set used in the NTM, and its 'long distance' trips include some that are less than 50 miles long. This different dataset was chosen by HS2 Ltd to enable effective and efficient modelling of the likely impacts of HS2.