text: Ihe proporti,ons for 1980 and 2000 are flon .Age aDd aex atrustule of urban and ruratpopulationa, 1970-2000! the 1980 a8EeasDentr (ESA/p/t{p.8I) t tbe proportions for 2025 are extrapolati.ons based on total populatron proJectrona anal ratios of urban to toCal populatlon 1n 1980. 1990 and 2000. g/ I'lore dee€loped r€gi.ons rnclude Northern Anerlca. itapan, all regionE ot 8u!ape,Australia, Nee Zealand and the Union of Sovi.et Socialibt Rapublics. l,eas developed regroo6 lnclude all reglona ot Aflica, all ragione ot IJatJ,n Aleri.ca, China, other countriea ot EaEt AEia, all reglona of South Aala, t{elaDeaia aDd Ulcronesla-Polyoesia. For the defj,nitions of the aub-regional conpooent8 of these reglona, see !E!:!l_Ipe:lg!li99._9l99e!9, pp. 38-39,A/40/5L9 English Page 96 198. rn the coming decades, a greater proportion of the working age population will be living in urban areag. iihereas less than one thirtl of the rdorklng age popul-ation in the less developed regions lived in urban areas in 1980, by the year 2000 about 45 per cent will be urban, and by 2025 the proportion rrill be alrDst two thirds. Among the least developed countries, the proportion li.ving in urban areas is projected to rise from 15.5 fo 48.5 per cent between 1980 and 2025- (i) New entrants to the working aoe populaEion 199. The l5-to-I9-year -old age group is of special interest, as it constitutes the new entrants to the working age population during each five-year period. At present about 80 per cent of this group are ln the less dev€loped regions, and this proportion 13 expected to increase to 84 per cent by the year 2000. Further, while the nu$ber of ls-to-I9-yea r --olds in the less developed regions will increase by 53 per cent by the year 2025. che nunber in the more developed region is projected to decrease, from 96 oilllon in 1980 to 90 million in 2025. In contrast, the 15-to-19-yea r -o1d age group in the 36 least developed countries is expected to
analysis: The text discusses population trends, urbanization, and demographic changes, which are all related to economic and social development. The proportion of the working-age population living in urban areas, new entrants to the workforce, and population projections for different regions are all key indicators of economic development and employment.