Despite considerable gender convergence over time, substantial gender inequality persists in all countries. Using Danish administrative data from 1980-2013 and an event study approach, we show that most of the remaining gender inequality in earnings is due to children. The arrival of children creates a gender gap in earnings of around 20% in the long run, driven in roughly equal proportions by labor force participation, hours of work, and wage rates. Underlying these "child penalties", we find clear dynamic impacts on occupation, promotion to manager, sector, and the family friendliness of the firm for women relative to men. Based on a dynamic decomposition framework, we show that the fraction of gender inequality caused by child penalties has increased dramatically over time, from about 40% in 1980 to about 80%in 2013. As a possible explanation for the persistence of child penalties, we show that they are transmitted through generations, from parents to daughters (but not sons), consistent with an influence of childhood environment in the formation of women's preferences over family and career.

Using Danish administrative data, we study the impacts of children on gender inequality in the labor market. The arrival of children creates a long-run gender gap in earnings of around 20 percent driven by hours worked, participation, and wage rates. We identify mechanisms driving these “child penalties” in terms of occupation, sector, and firm choices. We find that the fraction of gender inequality caused by child penalties has featured a dramatic increase over the last three to four decades. Finally, we show that child penalties are transmitted through generations, from parents to daughters, suggesting an influence of childhood environment on gender identity. (JEL D63, J13, J16, J22, J31, J71)

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We use historical publications and micro data from tax returns to construct internationally comparable estimates of the development in income inequality in Denmark over the last 140 years. The study shows that income inequality and top income shares have declined during several distinct phases in between periods of stability. Furthermore, the quality of the Danish data allows us to analyse not only the development in top income shares but also broader inequality measures such as the Gini coefficient. These analyses show that top income shares are a good proxy for the underlying development in inequality.

This paper investigates whether the impact of children on the labor market outcomes of women relative to men—child penalties—can be explained by the biological links between mother and child. We estimate child penalties in biological and adoptive families using event studies around the arrival of children and almost 40 years of adoption data from Denmark. Short-run child penalties are slightly larger for biological mothers than for adoptive mothers, but their long-run child penalties are virtually identical and precisely estimated. This suggests that biology is not a key driver of child-related gender gaps. (JEL J12, J13, J16)