[teamonkey]

My brain's frazzled. Are you using US gallons or Imperial gallons in those calculations?

I'd suggest they go a step further though. The first thing I do when looking for a new car is convert the mpg figures into pence per mile.

[frouaix]

I used US gallons.

[seano]

If they did that then the figures would change daily and be different for each market in which the car were sold.

[michaelneale]

if it could be done in a way you could see something updated a week, would be interesting - maybe would make people think twice before a longer trip (would work with me).