This trick requires using a custom Flag field to determine which tasks have a Finish By date entered for them. To display a symbol for Finish By dates in the Gantt Chart pane, you must a special trick. To set up the display of Finish By dates in the Gantt Chart pane, you will need to create a custom Flag field for this purpose, and then you will need to use the Bar Styles dialog to create the symbol.
This is similar to how Microsoft Project displays the green arrow symbol in the Gantt Chart pane for Deadline dates. To maximize the benefits of using a custom Finish By field to track “target dates” for completion of tasks, I recommend that you display a symbol for the Finish By dates in the Gantt Chart pane of your projects. Figure 3: Finish By date entered for major milestones Displaying the Finish By Date in the Gantt Chart Pane
