请将下面这段话翻译成英文：
人口老龄化(population ageing)是一个国家或地区年龄中值(median age)上升时出现的现象。其原因可能是人口寿命(life expectancy)的延长和/或出生率的下降。在不久的将来，亚洲和欧洲两个地区将有相当的国家面临人口老龄化问题。人口老龄化对经济造成的影响是相当大的。老年人比年轻人拥有更多的人均积蓄，但老年人在商品消费上花费较少。老龄化人口因此可能导致更低的利率。
参考翻译
Population ageing is a phenomenon that occurs when the median age rises in a country or region.The reason of it may be rising life expectancy and/or declining birth rates.In Asia and Europe,a significant number of countries will be confronted whh population ageing in the near future.The population ageing has a considerable effect on the economy.Older people have more savings than younger people.However,older people spend less on goods.As a result,an ageing population may thus lead to lower interest rates.
1.人口老龄化:可翻译为population ageing。
2.其原因可能是人口寿命的延长和/或出生率的下降:“人口寿命”可译为life expectancy;“出生率”可译为birth rates。
3.在不久的将来，亚洲和欧洲两个地区将有相当数量的因家面临人口老龄化问题:“不久的将来”可译in the near future；“相当数量的”可译为a significant number of;“面临"可译为be confronted with.
