Changes in life expectancy in the United States due to declines in mortality, 1968-1975.

This study examines the gains in life expectancy for four race/sex groups of the US population between 1968 and 1975. An increase of 2.3 years in life expectancy at birth and 1.7 years in life expectancy at age 45 years has occurred for all race/sex groups combined. The added years of life for the normal working ages (15-70 years) is only 0.6 years for the total US population, 0.3 years for white females, 0.6 years for white males, 1.5 years for nonwhite males, and 1.7 years for nonwhite females. The relative contribution of the five leading causes of death to this gain varies at different ages. For example, more than 50% of the increase in life expectancy at age 45 years was due to a lower mortality rate in diseases of the heart which is still the leading cause of death among each of the race/sex groups. Other contributions to the increase in life expectancy at age 45 years are: cerebrovascular diseases, 16%; accidents, 6%; influenza and pneumonia, 7%; and all other causes, 16%. The increase in the malignant neoplasms mortality rate had a negative effect, -2%, on the gain of life expectancy.