You can create crosstabs that show two different hierarchies of the same dimension in the rows and columns. Do this to isolate and analyze relative data at a fine level of granularity.
For example, you create a report that includes information on product vendors. The Vendor dimension in your report includes categories for each type of vendor, and an alternate hierarchy category that represents the vendors by region. Individual vendors are the lowest level in the Vendor dimension when filtered by vendor type. The By Region category includes location categories, including Europe, Far East, and Americas. Individual vendors are also the lowest level in the By Region category. When you create a crosstab that has Vendor in the rows and the alternate hierarchy By Region in the columns, you can quickly analyze the relative performance of the vendors in the different regions.