Reducing the infant mortality rate depends on getting out of poverty, and the line above with infant mortality rates stabilize is way higher than the $1.90/day

Reducing the infant mortality rate depends on getting out of poverty, and the line above with infant mortality rates stabilize is way higher than the $1.90/day definition of “poor” that is used in this article, in fact in a lot of the world, the income needed to escape high infant mortality is as high as what the authors of the posted article have decided to call “middle class”. See for example https://neweconomics.org/uploads/files/RBPLTechPub.pdf https://neweconomics.org/uploads/files/RBPLTechPub.pdf