The government’s plan to introduce 12 road tax (VED) bands instead of six is sensible, but the price of taxing a car in each band appears to have been generated at random. The changes in road tax (technically known as Vehicle Excise Duty or VED) are intended to persuade consumers to buy less polluting cars, by making road tax progressively more expensive for higher polluting models.

However, looking at the price jumps from one band to the next (the fourth column in the table) shows there is absolutely no consistent pattern to the increases – especially when EU emissions targets are taken into account.VED CO2 VED annual Increase from market share
Band g/kkm cost £ previous band £ 2007%

Band A up to 100 0 0 0.01%
Band B 101 - 110 20 20 2.33%
Band C 111 - 120 35 15 3.09%
Band D 121 - 130 95 60 4.97%
Band E 131 - 140 115 20 14.34%
Band F 141 - 150 125 10 14.96%
Band G 151 - 160 155 30 17.20%
Band H 161 - 170 180 25 10.20%
Band I 171 - 180 210 30 10.21%
Band J 181 - 200 270 60 10.75%
Band K 201 - 225 310 40 5.64%
Band L 226 - 255 430 120 2.88%
Band M 256 plus 455 25 3.42%

Proportionately, the biggest tax increase is the £60 from Band C to D – yet Band D is exactly where the EU says most cars should be (the EU proposal is for an average of 130g/km for all cars by 2012).

For the most polluting cars (Band M), there is only an additional £25 penalty, so a Porsche Cayenne Turbo with 358 g/km of CO2 will pay only fractionally more than a Band L Renault Espace 2.0 T Auto emitting 234 g/km of CO2.

That’s politics for you.