The term structure of population means age wise and sex-wise composition of the population along with the description of qualitative characteristics.
Age Structure of Population:
Age structure is an important characteristic of the population of a country or a region. The population is generally composed of different age group which greatly influence the social attitudes, economic activities, cultural trends, political vision and the military strength of a country. Normally percentage of the age-groups 1 to 14 and above 75 determine the economic development level of a nation. In developing countries, the population percentage of ages 1-14 is over 30 and ages above 75 is under 6 percent. On the other hand, in developed countries the percentage of ages 1-14 is over 30% is termed “Young Population” and that of above 30 years is called ageing population.
Human sex ratio:
According to Anthropologists and Demographers, the human sex ratio is the ratio of males to females in a population. More data are available for humans than for any other species, and the human sex ratio is more studied than that of any other species, but interpreting these statistics can be difficult.
Like most sexual species, the sex ratio in humans is close to 1:1. In humans, the natural ratio between males and females at birth is slightly biased towards the male sex, is estimated to be about 1.05 or 1.06 or within a narrow range from 1.03 to 1.06 males/per female born. Sex imbalance may arise as a consequence of various factors including natural factors, exposure to pesticides and environmental contaminants, war casualties, sex-selective abortions, infanticides, aging, gendercide, and problems with birth registration.
The sex ratio for the entire world population is 101 males to 100 females (2018 est.). Depending upon which definition is used, between 0.018% and 1.7% of live births are intersex.
Human sex ratios, either at birth or in the population as a whole, are reported in any of four ways: the ratio of males to females, the ratio of females to males, the proportion of males, or the proportion of females. If there are 108,000 males and 100,000 females the ratio of males to females is 1.080 and the proportion of males is 51.9%. Scientific literature often uses the proportion of males. This article uses the ratio of males to females unless specified otherwise.