Flash news - todays people have higher standards and expectations of living than your grandma and grandpa. In particular - most people want college education for their kids. College education comes with tens of thousands in expenses and people are like "how am I gonna put 2 kids in college? I think I will have 1"

Another flash news for people who haven't had kids in daycare for a while - pricing for daycare means that for the first kid the mom could work and come ahead money wise. Second kid is about neutral (depending on location and salary, in some cases the mom comes ahead money wise, in other case she does not). Daycare pricing made us decide to have 1 kid - if we had 2 kids in daycare my wife would have been better off staying at home (which we could not afford and she did not want to do anyway).

Access to contraceptives make a significant difference as well.

The college explanation cannot be the full or even the main driver, because countries with free college (+ scholarships) have the same issue. Same for daycare pricing.

> if we had 2 kids in daycare my wife would have been better off staying at home (which we could not afford and she did not want to do anyway).

Why the sexist idea that only your wife you could stay home? There are a growing number of men who are staying home to raise their kids - still a minority, but a good trend to encourage.

Of course I have no idea what your personal situation is. You may have made the best choice for your situation - but you implied you didn't even consider one of your options and that is bad.