[holding answer 16 October 2007]: The Office of Rail Regulation monitors fares nationally and publishes these quarterly in National Rail Trends at the following link.
Regulated fares are on average, 1.6 per cent. cheaper in real terms than 10 years ago. Regulated fares are increased by an average of RPI+1 per cent. Where fares are unregulated, train operators must price these competitively against other operators and other modes.