I'm not disagreeing with you, I don't think. I'm just pointing out that I don't think people having less kids means that they are poorer. As you pointed out,

I'm not disagreeing with you, I don't think. I'm just pointing out that I don't think people having less kids means that they are poorer. As you pointed out, kids have gone from being profitable to being a cost, so it doesn't really matter how rich or poor people are, they will have less kids. Unless, I guess, the state heavily subsidizes, and it seems that this article is saying that the efforts thus far to increase fertility via subsidization have proved too little. But actually, I think the general theory is that people have less kids precisely because they are richer as opposed to being poorer, since they don't need kids in order to labor on the farm and don't need kids to pay for the parents retirement.