The top right corner shows the total time within the simulation
required to arrive at this viewpoint shot from the
beginning.
The Duration shows the time required
during the simulation to arrive at this viewpoint shot from its
previous shot. The duration for a shot can zero or more. The
first shot, is set at 0 initially, although you can modify that
duration after the first shot is created. Once a shot's duration
has been modified, the total duration for the viewpoint is
updated.