"But China is ageing at an unprecedented pace. Because fewer children are being born as larger generations of adults are getting older, its median age will rise to 49 by 2050"
I see that as countering the lower birth rate temporarily, maybe until 2050? China has a lower life expectancy in rural areas and as the population continues to shift to city life expectancy will increase, thus a larger poipulation with more income. Kids don't have much income to spend.