关键词: 全面二孩政策, 生育水平, 总和生育率, 孩次递进总和生育率

Abstract: Based on China Migrants Dynamic Surveys from 2011 to 2018, this paper examines the fertility level and its changing trend of the floating population, and assesses the influence effect and internal mechanism of the universal twochild policy on the fertility level of floating population. The results show that the fertility level of floating population in China has fluctuated and increased since 2010, and the universal twochild policy has a significant impact on the secondchild fertility level of floating women. However, the accumulation effect of fertility caused by the policy was released quickly. In 2017, the fertility level of Chinas floating population reached a peak of 1.862, which was also the turning point when the fertility level turned from rise to decline. With the gradual implementation of the twochild policy, the secondchild fertility level of the floating population of different socioeconomic status has reversed: the secondchild fertility rate of the floating population with high socioeconomic status is lower at first, and then begins to approach or even surpass that of the low socioeconomic group. Studying the changes of fertility patterns among different groups caused by the universal two-child policy, we may shed light on the longterm development trend of China's population.

Keywords: The Universal Two-Child Policy, Fertility Level, Total Fertility Rate, Progressive Total Fertility Rate