<prompt> Translate the following text to EnglishWakati uzee wa idadi ya watu ni hoja ya kawaida ya kuongeza akiba ya kitaifa, baadhi ya wachambuzi wanadai kuwa kupungua kwa ukuaji wa nguvu za kazi kutaongeza uwiano wa mtaji na kazi na kupunguza kurudi kwa mtaji wakati wa kuongeza uzalishaji wa kazi.  <response>: While the aging of the population is a commonly voiced argument for raising national saving, some analysts maintain that the projected decline in labor force growth will increase the capital-labor ratio and reduce the return to capital while raising the productivity of labor. 