Dying is the one common and certain event in life but it is a difficult process to study. Official statistics give information about the point of death; studies covering random samples of deaths are inevitably retrospective and based on the accounts of those who knew the person who died; other studies are selective and generally focused on people dying from cancer, so they include a relatively small proportion of old people. Yet, in developed countries, deaths are concentrated among older people. In England and Wales in 1994 83.6% of all deaths were of people aged 65 or over; 59.0% were 75 or more.