Chain index an index number derived by relating the value at any given period to the value in the previous period rather than to a fixed base.
环比指数指通过把某一时期的数值与前一时期的数值相比，而不是与固定基期相比而得出的指数。
2
It points out that mutual value is the base for the parties to merge. The profit of the merged enterprise will not be made until a certain period of time.