Prediction And Application Of Population Size And Structure Combined With Birth Rate And Mortality Rate

As a country with a large population,China’s population issue has always been the core of the policy formulation and development planning.Population will have an important impact on China’s economic and social development,ecological environment balance and other aspects.The premise of the sustainable development of China’s total population is to maintain a reasonable population structure.Maintaining a balance in population size and structure is of great significance to China’s future economic and social stability and development.More than 50 years have passed since China began to implement the family planning population policy in 1971.The implementation of the family planning policy has slowed down the growth rate of China’s total population,improved the living standards of the Chinese people and the share of resources per capita,improved the quality of the people,and enabled China to experience a demographic dividend period of rapid economic development for 30 years.Since the 21 st century,China’s demographic,economic and social situation has undergone tremendous changes.The birth sex ratio of the population has been imba lanced,the fertility rate has decreased,the aging population has accelerated,and the labor force has declined.The demographic dividend has begun to turn into a population liability.Since then,population has influenced the further development of China’s economy and society.In this context,in December 2015,the comprehensive two-child policy was proposed,which will be officially implemented from January 1,2016,and the three-child policy will be implemented in 2021.Using the data of population mortality in China from 1994 to 2019 and the fertility data of women of childbearing age from 1997 to 2019,this paper establishes age-specific Chinese population mortality and fertility prediction models through the Lee-Carter model,and adjusts the model parameters.In the process of using the Lee-Carter model to establish the age-specific fertility rate model for women of childbearing age in China,the total fertility rate is used to constrain and adjust the model parameters.The predicted fertility rate is discussed and adjusted according to some possible trends of the future fertility rate.According to the results of age-specific fertility and mortality forecasts,combined with the age-specific population numbers,the age-shifting algorithm is used to predict the future total population.Finally,by calculating the age-specific population coefficient,population dependency ratio and drawing a population pyramid,the future of China will be predicted.The development of the population structure is analyzed.The research results show that with the increase of years,the mortality rate of the same age gradually decreases,the total birth rate of the population will show a steady decline in the next 40 to 50 years,and then increase,and the total population and labor force population coefficient show a downward trend.Based on the above conclusions,it provides information support for the adjustment of China’s population policy.