Remove grouping at intervals
Select the row or column field from which you want to remove grouping.
Click Properties on the PivotTable toolbar, and then click the Filter and Group tab.
Set Group items by to (No grouping).
Remove a custom group or custom group field
Do one of the following:
To remove a custom group, right-click the group caption, and then click Ungroup Items.
To remove a custom group field, right-click the field, and then click Delete.
Notes
You cannot right-click the Other item and ungroup it.
If the group you want to delete is the last custom group in the field, the custom group field will be deleted along with the group. If the group you delete is not the last custom group, the members of the deleted group will move to the Other group.