It's only been a few months since road tax was increased for cars in band 'G', but already there are calls for a new, higher band for the highest-polluting cars.
Currently, cars are ranked in bands from A to G, with the lowest carbon dioxide polluters in band 'A' and the highest - those that emit over 225g/km of carbon dioxide - in band 'G'.
Now, though, some feel there's a need for a newer band. Almost all cars on sale - 99.8% - emit between 100g/km and 450g/km, yet the top tax band is set at only 226g/km.
That means someone buying a Land Rover Discovery TDV6 (244g/km) pays the same road tax as someone with a Range Rover Supercharged 4.2 V8 (376g/km - a 54% increase) - so there's no incentive for luxury car buyers to downsize.
This has led for calls for a new tax band 'H' to be introduced, set at roughly 275g/km and costing £500 per year.
'This would give luxury car buyers an incentive to think about carbon dioxide outputs. At present, virtually every car on their shopping list is in band G, so why would they consider carbon dioxide emissions when buying a car?', said motor industry analyst Jay Nagley.
Even with band 'H' set at £500, owners of these expensive cars could afford the tax, so it's not the cost of the tax that's the deterrent.
Instead, cars in band 'H' would be worth thousands of pounds less at resale time than those in band G, and it's this drop in value that would make buyers of such cars think twice.
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