Simulating population development under new fertility policy in China based on system dynamics model

摘要

Abstract Fertility policy in China has been adjusted frequently in the past years by proposing innovative reformations because of various population crises. Aiming at relieving the population ageing, two-child fertility policy was implemented this year. The effect of new fertility policy is urgent to be checked. The system dynamics model is established on the basis of Song Jian population development equation, then simulation experiments are made for testing the new fertility policy. The results show that total population will peak at 1.448 billion in 2022 and reduce to 0.961 billion in 2050 under the regulation of the new fertility policy. However, population structure can only be moderate optimized, cannot be solved essentially. Furthermore, according to the comparative analyses among three different possible fertility policies, the two-child fertility policy enacted in china is verified to be reasonable. Finally, the sensitivity analysis on the willingness of having the second child of fertile women is made. Therefore, some specific measures are proposed as important suggestions for the fertility policy tracking.