Method for aid driving a motor vehicle

The invention relates to a method for calculating an index (i) of severity reflecting both the severity of the operation of a motor vehicle, and the severity of Use aids comfort of the vehicle, such as air conditioning, system audio / video, the index (i) of severity is calculated from energy consumption (Edepensee) of the engine relative to the distance traveled. This index (i) of severity is communicated to the driver using graphic means (8) or audio (9) so that the driver can adapt his driving based on this index.