...
Double-click the job box and you'll see a pop-up box where you can edit the dates and completion percentage.
Adjusting the dates and completion percentage
...
Another way to adjust the completion percentage is to hover the mouse cursor over the box until you see the little triangle which you can drag right or left to adjust accordingly.
Adjusting the completion percentage by dragging the triangle icon
...
Note: You can drag it all the way across to the left side to completely hide the task list if preferred.
Resizing the Gantt Chart
