decennial index

例句：

1. 1. The stockmarket has been trending upward for the past decade.
   过去十年，股市一直在上涨。
2. 2.The economic growth rate is calculated using a decennial index of GDP per capita.
   经济增长率是通过人均国内生产总值的十年期指数计算得出的。
3. 3. The researchers used the decennial index to track the population's aging trends.
   研究人员使用十年期指数来追踪人口老龄化的趋势。