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Economic progress has caused the opportunity cost of having kids to increase. Women have more options than ever when it comes to how to spend their time, money, and energy.
As Christine Percheski, associate professor of sociology at Northwestern University, told Insider, the declining birth rate is "about women having access to education and employment opportunities. It's about the rise in individualism. It's about the rise in women's autonomy and a change in values."
Trends in the 21st-century economy — especially the rise of dating apps — have combined with a higher level of education and more career opportunities for women to push marriage and childbearing so far off that it sometimes never materializes. Millennial women are about four times as likely as women from the Silent generation to have completed as much education at the same age.
The more educated a woman gets, the more likely she is to postpone having a child until her 30s. While that's partly explained by student debt, it's also because women today have more life options than women did 50 years ago.
It's opened up new areas for fulfillment. As Gina Tomaine wrote for Philly Mag, millennials like to be unencumbered and their economic experiences have made them question what makes a successful, meaningful life.
"Maybe a full, rich life is one that's overflowing with creativity, travel, exploration — all stuff that kids make more difficult," she pondered.