Abstract: | Abstract Empirical expressions derived by Coale and Demeny accurately characterized the relationships among death rates of different age groups for each sex during an extended period of time in Western nations. However, the relationships have changed in recent years, as the mortality of older persons has increasingly exceeded the level expected on the basis of these expressions. The recent disruption is relatively small for females and may be due to very rapid declines in maternal mortality. Among males, the change has been quite pronounced, and it is suggested that increases in cigarette consumption are largely responsible. |