日本按受教育程度划分的终身生育水平趋势：利用人口普查数据测算人口指标的新方法

This paper proposes a method for estimating the distribution of completed parity by combining information on co-residing children across multiple censuses. Applying the method to the Japanese population censuses conducted from 1980 to 2020, we construct data on completed parity and completed fertility rates, by single year of birth and educational attainment, for women born between 1940 and 1980. The data reveal five key findings. First, completed fertility declined from 2.0 for the 1955 cohort to 1.4 for the 1970 cohort and then leveled off. The expansion of higher education accounts for only about 5 percent of the decline, while most of the decline reflects behavioral changes within educational groups. Second, the parity distribution shifted from one centered on two children to one with a high share of childless women. Third, an average decline in mothers’ mean completed parity, an increase in lifetime unmarried rate, and increase in lifetime childlessness among married women each account for about one-third of the fertility decline. Fourth, many of the additional lifetime unmarried women lived with their parents at age 50. Fifth, among lifetime unmarried women living with their parents, the proportion whose primary activity is “work” has remained high, while the proportion whose primary activity is “housework” has declined. These patterns are observed regardless of educational attainment, although the contribution of each factor differed across educational groups.