According to the latest analysis by Glass's, the residual values of prestige sports utility vehicles (SUVs) continue to outperform the wider used car market, despite recent increases in availability.

Although many of these vehicles have experienced modest falls in their residual values over the past year, models like the BMW X5, Lexus RX300, Porsche Cayenne and Volvo XC90 still retain over 80% of their original cost (as a trade value) after a year and 12,000 miles.

"Registrations of prestige SUVs have more than doubled since 2001, and manufacturers continue to produce new models in response to high levels of demand," says Richard Crosthwaite, prestige car editor at Glass's.

"However, the prestige 4x4 sector is still relatively small - accounting for below 2% of the total new car market in 2004 - and their relative rarity helps underpin strong residual values."

Glass's predicts that values in this sector will ease back over the next year, but that they will continue to outperform the market in general, helped by the arrival of new models such as the Audi Q7 and the Range Rover Sport.

Nevertheless, so long as the increases in volume are maintained at sensible levels by manufacturers, the impact on values will be relatively modest," says Crosthwaite.