In the image below you can see how the rows are arranged on the table.

Grouping is only done by that value for one row.

You should get a result similar to the image below. All values for a given row are represented at one level.

Specifies the S2 column.

The cross table is grouped vertically into two levels.

Cross tables do not allow you to specify columns or rows. For example, if no columns are specified, grouping is done by rows. For some reports this property is very important for cross tables. The following figure shows one of those reports.