This article describes how to go from a standard table with a NET at the bottom...
...to a table where the NET has been moved to the top:
A table with rows.
1. Select your table.
2. Go to Properties > RULES on the object inspector.
3. To apply the rule, select the Plus (+) > Sort/Reorder Rows or Columns > Move NET Row to the Top > OK.
Note, if you have a crosstab and select Switch rows and columns on your table, the rule will apply to what was previously the column NET instead.