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Data sets in a variable data hierarchy have no fixed sequence as they do in a fixed data hierarchy. The data sets in a variable data hierarchy can be rearranged in many different ways that change the parent - subordinate relationships. The aggregated data in variable data hierarchies change according to the hierarchy of data.
Unlike summary data, aggregated data in variable data hierarchies are not named according to the data set in which they appear. They are named according to the parent data sets above the data set where they are located. The name of the data set where aggregated data appears must represent the parent data sets.