Car transaction prices in January fell by 0.36 per cent according to the latest figures from CarPriceCheck.com.

But the downward pressure on margins is heavier than the figures would suggest, the company says. By including surplus 2002 model year stock, and vehicles in the process of being replaced (such as the Renault Megane Scenic and Toyota Avensis) transaction prices actually plummeted by 1.78 per cent over the same period.

"These models will find their way into the market by hook or by crook," says Steve Evans of CarPriceCheck.com. "Manufacturers simply cannot afford to be weighed down much longer, especially with the new March registration plate just weeks away."