I did an internet search a few days ago and readily found some figures about UK new car registrations with sector percentages.
Sadly I didn't save the actual data but in essence since 1980 we have been registering 1.5 - 2.5 million cars a year
During that time the figures would suggest that cars in the 4x4 category equated to 3-4% on average , peaking in at 8% in 2006 I think.
That suggests that in relative terms the number of so called 4x4 on the road is relatively low.
Granted some of those 4x4 are in the top level of polluters but others are not , some sit only just higher than some family saloons , so there is a broad cross section.
My point is that 4x4s are the not cause of Global warming , the damage was done 200 years ago by our ancestors. Yes high polluting cars will not be helping but dont loose site of the fact that no matter what car you drive its polluting in some way just a little less.
As its been said the car you drive is not the only factor , how you drive , where you drive and how far you drive will all be a factor.
I do 14000 miles a year , my boss , in her Avensis diesel, does close to 40000 a year , despite my high Co2 and her low Co2 she puts out more pollution than me.
Yet no one seems to want to take that into account
When will some actually understand that the tax based on CO2 is not aimed at 4X4s, if that was the case then surely they could tax the use of 4WD as against 2WD. Its based on fuel burned per KM to move a object!
So but your maths head on, what does that tell you.