After you create a schedule, you may want to change its organization and structure by grouping columns. You can create several layers of headings and subheadings to provide more detail in your schedule.
Be sure the cursor appears as an arrowhead as you select the headings, as shown in the following image.
A new heading row displays above the grouped column headings, as shown in the following image.
Text in the new heading row is centered.
To modify the text in a column group heading, click the heading field and edit the text. To delete the column heading row, select the heading and, click Modify Schedule/Quantities tabHeaders panelUngroup, or right-click in the heading cell, and click Ungroup Headers.