the.com/dependency ratio
the math of how many mouths each working mouth must feed.
means the number of children and elderly per 100 working-age adults in a population, a blunt gauge of economic burden per worker.
from emerged in 20th century demography and actuarial science as governments needed a shorthand for how many non-workers a shrinking or growing labor force would have to support, especially for pensions.
formula basicsunder 15s plus over 64s, divided by 15-64s
japan extremejapan's ratio now exceeds 70 per 100 workers
africa inverseniger's youth bulge gives it one of world's highest ratios
china's pivotone-child policy flipped its ratio from asset to liability
for instance
japan 2023 — dependency ratio near 71, driven by elderly, not children
niger — ratio over 100, mostly from a young, fast-growing population
china aging shift — working-age share peaked around 2010, ratio climbing since
nigeria youth bulge — high ratio from under-15s, a demographic dividend in waiting