A model for successively forecasting and monitoring the development in the number of fatalities in traffic is presented. The model has been created through time series analysis covering the years 1977-1991. The model is simple, with the number of fatalities as the dependent variable and with time and traffic as the only predictors. The time factor describes the cumulative effect of changes such as better roads, vehicles, drivers, etc. The model is multiplicative and permits a nonproportional relationship with traffic volume. Taking into account the purely random fluctuations in the number of fatalities, the historical fit for the period 1977-1991 is very good. Also the forecasts for 1992 and 1993 have proved very accurate. The model will be revised as new annual data are received. At present, the model points to a favorable development in the reduction of the number of fatalities up to the year 2000, assuming a moderate increase in traffic. (A)
Abstract