Japan and China, to the best of my recollection, have heavier "old age heavy" population dynamics than the US. Years of one child only policy in China have left large chunks of their country with the expected 2-1 ratio that has resulted in a second generation 4:1 ratio from what I was told by a friend in the investment business.
Take a look at India. Billion people, huge potential. Massive problems with infrastructure and their freshwater supply is strongly influenced by any changes in global warming since they are tied to a degree to glacial melt.
"That's what." ~She