Why is the total fertility rate so low in Puerto Rico?

Question

The World Bank estimate of 2018 puts the Puerto Rico which is ranked separately from the U.S. in 199th place out of 185 sovereign states and 15 separately listed dependencies in total fertility rate (approximately total number of children born per lifetime at current birth rates adjusted for age) with a TFR of 1.0.

Why is Puerto Rico at the bottom of this list? (The remainder of the U.S. is in 145th place and significantly higher.)

It isn't nearly as urban as countries like South Korea and Japan with very low TFR, and its per capita income is much lower than the rest of the U.S. which is usually associated with higher TFR.

Answer 1

This is largely due to the extremely high levels of migration to the mainland United States. That's been happening for decades, but until recently was offset by an extremely high birth rate among Puerto Rican woman- the average Puerto Rican woman was having five or more children as late as the 1960's. And then migration to the mainland rocketed up during the 2010's economic crisis, and then again after Hurricane Maria.

Migration is typically a young person's game. Older people set down roots and have homes, property, and careers that make them much less likely than young people to move. As a result, Puerto Rico's population is steadily getting older while the people of child-bearing are leaving the island to settle elsewhere. The single, older woman who isn't having children counts against the fertility rate, while the young women who settles down in Philly and has a child there adds nothings.