This example demonstrates how r.a.d.grid can be bound to pivot table. This is especially useful when you want to display the data in a reverse order but still keep the same presentation and structure in the source table. The logic resides in the PivotTable method in the code-behind of the page which transforms the table rows into columns and the table columns into rows in the rendered grid.
Note, however, that features like paging, sorting, grouping, filtering, etc. will behave in a different way because the type of the data in the grid columns can vary (for example integers, strings, dates, etc.). This is due to the "vertical grid" effect. That is why sometimes they may return unexpected results and you should consider whether to enable them or execute your custom logic to manipulate the data in the grid.

You may also review the relevant article from the product documentation:
Displaying pivot data