In general, the age group referred to when people talk or write about older adult drivers is the one of 75 years and above. Previously, it was the group of people aged 65 years and above. The reason for this shift in age groups is that older people are becoming more vital: today's 75-year-olds are as vital as the 65-year-olds were in the past. This is reflected in their fatality rate. Nevertheless, using rigid age boundaries does not take into consideration the fact that ageing is a process that does not start at the same age for each and every individual, nor progresses at the same pace. There can be large differences in driving skills between people of the same age, as well as in their physical and mental abilities. It is very well possible that some 85-year-olds are in better shape than certain 40-year-olds.