As a result of economic development, the public has increased revenue. Well-being, food nutrition, which is essentially hygienic. The population has good living standards, education, technological and medical advancements, which will result in people making healthier people healthier. The mortality rate has reduced the population to longevity, allowing the world to enter the elderly society, according to the pyramids of the world's population. The structure of the world's population has changed. In the range of older people, it expands.
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