Use selection-based sets to position one or more items from a dimension adjacent to each other in the crosstab for a mixed grain comparison.
For example, you can select items from a single dimension like this in the source tree.
You can drag these items to the crosstab.
You can also nest items from the multiple levels of the
same dimension 
.
In the source tree, expand the dimension to locate the items that you want to insert.
Press Shift+click or Ctrl+click to select multiple items in a dimension and then drag them to the crosstab.
A selection-based set appears in the crosstab.
