https://www.statista.com/statistics/241530/birth-rate-by-family-income-in-the-us/
Birth rate in the United States in 2017, by household income
Income and high birth rates are strongly linked, not just in the United
States, but around the world.
As the income scale increases, the birth rate decreases
根據美國在2017年的統計 家庭收入越高生育率越低