物价指数是反映不同时期(作为比较基础的时期,叫基期,与之进行对比的时期,叫报告期或计算期)商品价格水平变动方向和变动程度的相对数。物价指数通常用百分比表示,说明计算期比基期物价水平上升或下降百分之若干。因为指数必然用百分比的形式表示,所以不再在指数后使用百分比符 Price index is the relative number of changes in the direction and extent of changes in the level of commodity prices, reflecting the different periods (as a base period, called the base period, compared with the period, called the reporting period or calculation period). Price index is usually expressed as a percentage, indicating that the calculation period than the base price level rise or fall by a few percent. Because the index must be expressed as a percentage, no longer use the percent sign after the index