Trends in aggressivity of the Australian light vehicle fleet by year of manufacture and market group: 1964 to 2000

Monash University Accident Research Centre - Report No. 214

Authors:  S. Newstead, L. Watson & M. Cameron

Full report in .pdf format [280KB]


Aggressivity ratings measure the serious injury risk vehicles pose to drivers of other vehicles with which they collide. The relationship between vehicle aggressivity and the year of manufacture of Australian passenger and light commercial vehicles manufactured from 1964 to 2000 was investigated. Trends were examined by year of manufacture both for the fleet as a whole and by market group for vehicles manufactured from 1982 to 2000.

The aggressivity ratings used were based on data on crashes in Victoria and New South Wales during 1987-2000 and in Queensland and Western Australia during 1991-2000. Aggressivity was measured by a combination of injury severity (of injured drivers) and injury risk (of drivers involved in crashes). The ratings were adjusted for the sex and age of the focus driver (i.e. the driver of the vehicle impacted by the vehicle of the specific year of manufacture and / or market group), the speed limit at the crash location, the state in which the crash occurred and the year in which the crash occurred. These factors were strongly related to injury risk and/or severity for aggressivity. The aggressivity rating estimates the risk of the focus driver being killed or admitted to hospital when involved in a tow-away crash, to a degree of accuracy represented by the confidence limits of the rating in each case.

The results of this report are based on a number of assumptions and warrant a number of qualifications that should be noted.

Sponsoring Organisations - This project was funded as contract research by the following organisations: Road Traffic Authority of NSW. Royal Automobile Club of Victoria Ltd. NRMA Ltd. Transport Accident Commission. Royal Automobile Club of Western Australia Ltd. and by a grant from the Australian Transport Safety Bureau