An important new paper by Geruso and Spears looks at how much of fertility decline is explained by childlessness versus smaller family sizes. "Childlessness explains only 38% of the decline in fertility in the advanced economies." This implies larger families may hold the key! 🧵

The paper found a high correlation between the average number of children for all women and the average number of children only for mothers. Meanwhile the relationship between the average number of children and childlessness was weaker. 2/4

This suggests that to increase the birthrate of a country, it may be much more fruitful to encourage existing parents to have more children than to get the childless to become parents. That also seems easier, since the childless often have numerous barriers to parenthood. 3/4