text: Graph of the changing time of mid-day for Charleston, South Carolina (USA) and Santiago, Chile.  Note how, in both cities, the time of mid-day drifts backwards against the clock by about 25 minutes during the period from mid-November to mid-January.  If the day length were unchanging, then this perihelion drift would cause the sun to set 25 minutes later during this period; it would also cause the sun to rise 25 minutes later.  The combination of this perihelion drift and the changing length of daylight near the solstice is what causes the complex effects involving the times of sunrise and sunset at this time of year.  Data from the US Naval Observatory.