To optimize calculation performance, order the sparse dimensions in the outline by their number of members, starting with the dimension that contains the fewest.
See Designing for Calculation Performance.
The outline in Figure 32, Designing an Outline for Optimized Calculation Times is designed for optimum calculation performance:
The smallest standard dimension that is sparse, Market, is the first of the sparse dimensions in the outline.
The largest standard dimension that is sparse, Product, is immediately above the first attribute dimension. If the outline did not contain attribute dimensions, the Product dimension would be at the end of the outline.