Fig. 1From: Decomposing contribution of age and non-age factors to rapid growth of lung cancer in Xuanwei over past 30 yearsThe people pyramid of Xuan Wei in three periods. a composition of the population(horizontal axis) and age groups(vertical axis) in 1973–1975. b composition of the population(horizontal axis) and age groups(vertical axis) in 1990–1992. c composition of the population (horizontal axis) and age groups(vertical axis) in 2004–2005Back to article page