What are the Reliability History charts?
The chart for an individual model will tell you where a model’s strengths and weaknesses have been. Scores are based on the percentage of survey respondents who reported problems for that trouble spot, compared with the average model of that year. Models with problem rates close to the mean receive a for that trouble spot. Models with scores of or are not necessarily unreliable, but they have a higher rate of problems than the average model. Similarly, models that score are not necessarily problem-free, but they had relatively few problems compared with the average model. In particular, within each trouble spot and within each model year, we create equal-width intervals for the , , , and , constructed so that the average model is the middle of the , and the interval for the begins at 0 percent. An exception to this rule occurs when the mean problem rate is quite small (less than 2.5 percent), as is often the case in newer model years. In order to avoid making distinctions that are too
