简介:AgeStructureandDependencyRatioChina’spopulationhasexperiencedaprocesfromahighbirthrateandhighmortalityratetoalowbirthrateandl...
简介:ProjectionofChangeintheAgeStructureoftheWorldPopulationBythemid-21stcentury,theworldpopulationisprojectedtotoptenbillion,ofwh...