Why do some countries have negative population growth?

In a certain period of time, the total population of a country or region is shrinking, that is, the growth rate is negative. Negative population growth is divided into natural population growth and unnatural population growth. Natural negative population growth refers to the state that the total population decreases because the number of births is less than the number of deaths when the foreign population is excluded or assumed to be zero. Unnatural negative population growth refers to the state that the number of migrants is greater than that of floating population, which leads to negative population migration, also known as negative population migration. There may be five combinations of negative population growth: (1) natural positive growth and unnatural negative growth, but the net migration is greater than natural growth. (2) Natural growth rate is zero, and unnatural negative growth. (3) Natural negative growth and unnatural growth rate are zero. (4) Natural negative growth and unnatural positive growth, and the floating population is less than natural decrease. (5) Natural negative growth and unnatural negative growth. Studying the different combination types of negative population growth in a country or region is helpful to formulate countermeasures in line with the coordinated development of social economy and population in that country or region.

The main reason? It should be because highly developed people no longer need support, they are too busy to raise children and have good medical and health conditions.