1 PricewaterhouseCoopers 2010.
2 OECD 2006. The OECD splits land transport into two sectors in this report, which is why we refer to "five" sectors here.
3 CIA 2010.
4 The OECD countries are Australia, Austria, Belgium, Canada, Chile, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Korea, Luxembourg, Mexico, the Netherlands, New Zealand, Norway, Poland, Portugal, Slovak Republic, Spain, Sweden, Switzerland, Turkey, the United Kingdom, and the United States.
5 World Bank Group 2008.
6 US DOT 2010.
7 World Bank 2008.
8 HM Treasury 2009.
9 HM Treasury 2006.
10 Ernst & Young 2007.