The upper-medium car sector has seen the largest price increases over the past 12 months.
The report says that after two years of virtual price stagnation, the last four months have seen sizeable price rises across many models, equivalent to an average year-on-year rise of 2.7%, or an additional £432 for each car.
The lower-medium car segment has also seen increases, with five of the big sellers (Ford Focus, Vauxhall Astra, VW Golf, Toyota Corolla and Citroen C4) replacing outgoing variants in the class at a higher price point. In addition, the emergence of a new generation of 'MPV-style' compact family cars has further helped push up average prices in the sector.
The price of the average supermini (e.g. Ford Fiesta, Peugeot 206) fell by 0.4%, or £43 over the past year, in part reflecting the arrival of new vehicles at the budget end of the market.
Overall the executive sector (BMW 3 Series, Audi A4, etc) has changed little down 0.1%, representing a fall worth £13.
The single biggest list price rise in May was for the Nissan 350Z 3.5 V6 Coupe, which rose by £500, or 2%, to £25,297.
The largest single list price reduction last month was for the Chevrolet Kalos 1.4 Sport three-door, which fell £305, or 3.2%, to £9,807.