For more information on data sources and other articles see:

Valuing Household Transport in the UK

http://www.statistics.gov.uk/themes/economy/Articles/General/extracts/dec01.asp#valuing

Department for Transport, Local Government and the Regions (DTLR)

http://www.dtlr.gov.uk

Labour Force Survey

http://www.statistics.gov.uk/ssd/surveys/labour_force_survey.asp

National Travel Survey

http://www.statistics.gov.uk/ssd/surveys/national_travel_survey.asp