Passenger traffic deserves pride of place in any consideration of British Rail's future revenue because, although freight and parcels accounted for over half of railway revenue up to 1970, the position has since been reversed. In addition, growth prospects are brightest for passenger traffic. Rail passenger services can be divided into four broad categories. Firstly, there are Inter-City express services, operating over about 4000 miles of BR's network and producing 44% of passenger revenue (excluding revenue from subsidies) in 1973. They received almost no financial support from the Government under the 1968 Transport Act, in contrast with the other passenger services, most of which were subsidised. Secondly, there are the London and South-East services which accounted for 45% of fare revenue in 1973. The London and South-East network includes most commuter and express services in the Southern Region, together with commuter services in an area extending for about 40 miles around North London. Thirdly, there are commuter services in the other main conurbations. Responsibility for these rests, under Section 20 of the 1968 Act, with the Passenger Transport Executives (PTEs), who must bear the losses incurred, although these were supported by a 70% Central Government grant in 1974. The PTEs decide on the levels of service and fares, but BR remains responsible for the actual operation of these lines. Finally, the remaining subsidised services include local services not in the conurbations, stopping services on main lines, cross-country and secondary services, and rural branch services.