More people are leaving their cars at home and taking the bus, according to Keith Ludeman, the chief executive of public transport group Go-Ahead."Whilst rail remains difficult to predict, we now expect our full year operating profit across our rail and bus businesses to be higher than we previously anticipated and around the same as achieved last year (FY'10: £101.0m)." Ludeman said.The group saw revenue rise 6.0% at the interim stage to £1,132.2m from £1,068.4m in the second half of 2009."Like-for-like passenger numbers increased by 1.7% to well over one billion per annum. Our bus operating profit is at record levels and is a strong indication of people leaving their cars at home and taking the bus," said Ludeman.Profit before tax in the six months to 1 January 2010 edged up 1.4% to £50.7m from £50.0m the year before. Underlying profit was slightly ahead of management's expectations at £59.0m, up 8.9% from £54.2m in the latter half of 2009, despite the 2010 period being one week shorter than the 2009 period.Net debt fell to £71.6m at the end of the reporting period from £88.3m at 3 July 2010.The bus division saw revenue rise to £320.6m from £314.3m, while operating profit climbed to £36.9m from £34.3m. Operating margin improved to 11.5% from 10.9%.The rail division's revenue rose to £811.6m from £754.1m. Underlying operating revenue jumped to £22.1m from £19.9m, while the margin ticked up to 2.7% from 2.6%.The group expects first half rail revenue growth trends to continue in the second half.The interim dividend has been held at 25.5p, but there is no special additional dividend of 25.5p this time round.