The total fertility rate in Seoul, South Korea, was recently 0.55. This gets attention, but close behind it, with TFRs <1.0, are Hong Kong, Taiwan, Singapore, Beijing and Shanghai.
This means that, in each generation, the population would fall by about 72%. But, a woman doesn’t have 0.55 children. Here’s one example:
To get a TFR of 0.54, you would need 60% of women to have zero children; 28% of women to have one child; 10% of women to have two children; and 2% of women to have three children.
This is pretty amazing. 60% of women have no children at all. Only 12% have two or more.
Here’s another example, producing a TFR of 1.0, just to get an idea of what that means in real life:
Not all women are professional class. Those in the professional class have tended to have much lower fertility than the population as a whole. So, for high-earning women, take these numbers down further.
Cornerstone 