In all likelihood, this will exacerbate the population decline as many young men will simply emigrate to other areas. For China, since it is technically a growing economy, moving from an agrarian system to one that is more capitalistic, they may be able to absorb some of that with economic gains offsetting population demographic changes. But that is hard to say. China is very secretive about its economy and its banking sector. Many economists fear that things are far more tenuous with their economy and that their shadow banking industry has too much exposure to bad debt.
You can thank Deng Xiaoping for both opening the economy to a form of capitalism, which has undoubtedly brought millions out of poverty, but also while still retaining glimpses of its former self through a strict, government-controlled economy (Command Economy). He was the primary architect.
Its no secret that they prop their economy up through building projects that serve no other purpose than to raise GDP. They're GDP is very strong, but like the US they're taking on so much debt that its built on a house of cards.
And, as has been pointed out, their selective abortion campaign (kill all females or any male born with a male sibling) has really bitten them in the ass. There are millions of single, sexually frustrated men roaming around China with no mates or even potential mates. How could no one not see that coming? Naturally their population will decrease while India's will still soar... the projections in the graphic make sense to me.
Japan however is in a terrible quagmire. Their economy is mature and they have been struggling with growth for decades now. With a non-existent immigration policy and nightmarish debt levels, I can't see how things will end well for them.
Oh yeah... Their workforce is diminishing and it will not be able to support an aging population. They're whole obsession with virtual reality is seriously problematic. They don't fucking procreate!!! So we'll see this inverted pyramid where a tiny labor force is trying to sustain an enormous elderly population of pensioners. They'll be no money to support them.
"Reason obeys itself; and ignorance submits to whatever is dictated to it" -- Thomas Paine
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