Average used car values are lower than the 12 months previously for the first time this year, according to CAP, and so de-fleeting three-year old cars now could mean a 3% loss over de-fleeting at the same time last year.

Smaller cars have seen the largest year-on-year reductions in value; a typical supermini is now almost 10% less valuable than the exact equivalent vehicle in 2009. August figures show that the values of two further sectors have fallen, too. Upper medium and small executive models are typically less valuable than a year ago.

Mike Hind of CAP said: "Taking the used car market as a whole, values are now on average almost 3% lower than in August 2009. It is the first time this year that average values have been lower than 12 months previously.”

Cars across all sectors have fallen in value since April this year, gradually negating the price rises which occurred in 2009.