Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Using a compiled data set of 441 censuses and surveys from between 1787 and 2015, representing 103 countries and 51.4 million mothers, we find that: (i) the effect of fertility on labour supply is typically indistinguishable from zero at low levels of development and large and negative at higher levels of development, (ii) the negative gradient is stable across historical and contemporary data, and (iii) the results are robust to identification strategies, model specification, and data construction and scaling. Our results are consistent with changes in the sectoral and occupational structure of female jobs and a standard labour–leisure model.