The money taken in from fuel taxes far outweighs the subsidies for transport.
# Public subsidy support for buses in England outside London currently cost about £1,100 million a year
# Public subsidy for rail is broadly similar even though the bus carries about five times the number of passengers and delivers far greater social inclusion benefits
http://www.cfit.gov.uk/factsheets/13/index.htmSo public transport subsidies are about a tenth of the fuel duty. UK Fuel taxes are about two thirds of the price - so the subsidy is about one fifteenth of $6.40, or 40 cents.