Smoking in New Zealand: a census investigation.

New Zealand may well be unique in that in the 1976 and the 1981 Censuses of Population and Dwellings, persons over the age of 15 were asked about their cigarette smoking habits. The data are available on the basis of age and ethnicity, enabling an examination of the prevalence of ever-smoking by a cohort born some 80 years before the censuses were taken, at the end of the last century. Thus the effect of ever-smoking on mortality can be calculated. Ever regularly smoking reduced the life expectation of males by 11.7 years and females by 15.6 years. The corresponding reductions for Maori were 19.3 years and 23.8 years. The effect of smoking on health has been of epidemic proportions, notably for the Maori.