Distance driven is not a great metric in the case of cars or other road transport (it is for most transport) because conditions vary. If I drive the approx 200

Distance driven is not a great metric in the case of cars or other road transport (it is for most transport) because conditions vary. If I drive the approx 200 miles to central London I am at a far greater risk of having an accident in the crowded traffic of the last few miles than I am on the motorway on the way there. One big difference between the US most of Europe is that people tend to commute by car a lot less.