Notes
Unit costs derived using MARKAL costs £m per Bn veh km and converted using the following MARKAL annual km figures:
| Year 2005 | Annual km |
| 2Wheels | 5,536 |
| Car | 14,481 |
| Van | 20,272 |
| HGV | 54,000 |
| Bus | 63,537 |
| Rail (Passenger) | 186,000 |
| Rail (Freight) | 186,000 |
| Air (domestic) | 1,000,000 |
| Air (international) | 1,700,000 |