Mac OS Utilities
You may have to draw the schedule of a concert, or of any other kind of performance or program: iSchedule makes it easy for you to build any sort of schedules, since you can easily add and/or subtract hours, minutes and seconds.
Eventually you can save your schedules as text-files for future reference.
The screen-shot (below) shows the schedule of a concert whose expected duration is set to 1 hour 50 minutes (top line). You can see that the last row of the list is colored (red), since the overall duration of the concert is going to exceed the expected duration.
By the way, the application had been originally commisioned by a renown Italian musician to draw the schedules of his own concerts.