Rollup Variance . . .
Companies are organized into hierarchical structures. For example, Products roll up into Groups; Groups roll up into Divisions; Divisions roll up into a fully consolidated Company. In order to provide mathematical consistency (as well as an all important drill down capability), the use of a Rollup Variance accumulator is required. Rollup Variance functions as an accumlator of Mix Variances. Rollup Variance, at any level of consolidation is equal to [Rollup Variance plus Mix Variance] accumulation brought forward from the immediately preceding lower consolidation level. Note that Rollup Variance accumulation starts at 0 at the lowest (Product) level of the consolidation hierarchy.