Consistency of model year injury claim frequency results for selected 1981-1983 models.

This study compared the all-claims injury results data of 118 different vehicle series for at least two of the model years 1981-83. Of the 230 paired comparisons of individual model year data, 223 had claim frequency results that did not differ significantly. The seven paired comparisons that did indicate differences between model year results are within the number expected by change alone. Thus, this study demonstrates that the injury results for individual model when the basic vehicle designs are unchanged.