219' under this hypotheticar. exafirpre the proportioo of rhe total population in thelabour force changes moderately from 0.53 under high mortarity conaitions to justover 0,50 under lower mortality conditions. (If only the population aged 15 andover is considered, the proportion changes insignificantly from O.g7 to 0,86,suggesting that rnost of the decrease in relative labour supply is due to excessgroldth in the numbers of young dependents) . These proportions imply a decrine fromI.14 rdorkers available to supporc each dependent member of the population to1.01 workers as survivorship inproves from an expected Iife expectancy of 40 yearsat birth to one of 65 years at birth. This impties an 11.5 per cent decline inavailable workers per dependentt a corresponding increase in productivity rdould benecessary to retain the identical per capiea income. 220. l'lot onLy can the retative supply of rabour change during the transition fromhigh to low rnortar.ity but the age diitri.bution of those in the labour force mayalso be expected to change in ways that alter the distribution of rongevity in thelabour force and associated prod;ctivity, Surprisingly, hor,r,ever, the mean age ofthe labour force in the two itlustrative populitions-ii nearly iientical _35.8 years before onset of the mortality dectine and 35.2 years near itsconclusion. This constancy, however, masks change. MortaLity decline increasesthe proportion of workers j.n the younger and otder ages more or lesssymmetrically. The mean age renains the same but the distribution is broader. 221' rmprovement in mortarity and morbidity levers may bring vrith it improvenent inthe quality of the labour force necessary to counter-barance the smarl decrine inrelative labour supply. r.ower levels of infant and child mortality will result ina-9ain in the expeched returns from i.nvestments made during earry child-rearing.Since 1ow mortality increases returns per surviving child, the incentive forparents and society to make such investments in chikl health care and education isincreased. with increased investment, the qual,ity of labour supplieal and thequality of employment available will rise. 222. Human capital investment i.s not the only reason, of course, to expect apositive relationshj.p between hearth and productivity. A healtbier pe;son isA/ 40 /srg EngIi sh Page 103 Iikely to be physically stronger' oentally quicker and miss fewer days of rdor k due tq lllness. $hether one is employed, where one ls employed, what one can do on the
**Analysis**
The text discusses the impact of mortality decline on the labor force, population structure, and productivity. It highlights the changes in the proportion of workers, the age distribution of the labor force, and the expected improvements in the quality of the labor force due to investments in human capital. The text also mentions the relationship between health and productivity, suggesting that a healthier person is likely to be more productive.

**Category**
Employment, Health