Arizona's birth rate is falling faster than anywhere in America. Tom Rex, associate director of the Center for Competitiveness and Prosperity Research, a unit of the L. William Seidman Research Institute, explains one reason why in this article on CNN Money June 27, 2018:

Tom Rex, manager for research initiatives at Arizona State University's Office of the University Economist, says that's largely because Arizona was drawing in so many Mexican immigrants for work in tourism and construction.