The progressed duration and remaining duration of an activity displays in blue just before and after the data date line respectively. Both will display by default.

To turn these on or off, double-click or right-click the activity to open the Activity Object Window.
Select the Displays tab.
The Progressed and Remaining durations may be checked or un-checked to display or hide them respectively. This may be very useful as the positions of these are unable to be customized.
