Log in to the HTML5 client.
Select the Work workspace, Gantt tab.
Select a project in the Project Data Selector.
Select the task you want to track.
In the Task panel, select the Task Form tab (
).
In the Tracking section, select a value in the % Completed field.
Click on the Cmd (
) gear button of the task you want to track.
Select the Edit Task details command to open the Task Details dialog box.
In the Definition folder, Tracking section, select a value in the % Completed field.
Place the mouse pointer on the task for which you want to enter the Completed Date.
Right-click to select the Update Completion command to open the Update Completion popup.
Select a date in the Completed Date field.
The % Completed will automatically be computed in the Task panel, Task Form tab, Tracking section.