title: The dependency ratio.
authors.forename: R N
authors.initials: RN
authors.lastname: Butler
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D003858:Dependency, Psychological; D004467:Economics; D006801:Humans; D008136:Longevity; D008875:Middle Aged; D011157:Population Dynamics; D014481:United States