One of the questions I am most frequently asked is which are the best performers in the various vehicle sectors, from our perspective. When this question comes from non-automotive professionals, it tends to mean which cars retain their value best.
This is the great obsession, especially among motoring writers, but a little knowledge is a dangerous thing and, while depreciation is absolutely central to the question of running costs, it is not the whole story.
It is, of course, simple to write about how a car retains 51% of its list price after three years and equally easy to forget that the car might cost an arm and a leg to fuel and service every year. It is also not as much fun to write about the bread and butter family steed which manages to retain only 37%.
The truly interesting numbers - those which really reveal the best performers - are the pence per mile figures. If you go to this year's Fleet Show you will, for the first time, see a line-up of some of the best ppm performers on a special 'Cap Class Leaders' stand.
These are cars that manage to strike the critical balance between residual value retention, manageable day-to-day fuel and maintenance costs and sensible cost new. It is a unique opportunity for the apparent 'saints and sinners' to rub shoulders in the same display - where a humble Perodua Nippa or Seat Cordoba and Arosa can sit proudly alongside the likes of BMW, Mercedes and Audi.