A Relative Time dimension is an example of a Utility dimension, a dimension that does not directly join to the data being analyzed, and is not directly used to slice and dice data. Rather, the Utility dimension assists the modeler (and user) by making the presentation of the model more user-friendly. An example of this is allowing the user to select a measure to show in the pivot they create (or report), by allowing them to select a dimension member (that is, the measure name from a list of options).
Consider the following screenshot, which shows a very simple proforma report with
Months on rows, and the product categories on columns. A Utility dimension allows the user to select the measure that ...