I just looked at the schedule, too. There are altogether 112 trains per day per direction. Of the southbound trains,

• 41 run the full distance,
  
• 25 start in Beijing but don't reach Shanghai,
  
• 42 start somewhere south of Beijing but reach Shanghai, and
  
• 4 use some section in the middle only.

The busiest section is the south end, Nanjing–Shanghai, which also carries the east-west traffic of the corridor along the Yangze River (83 southbound trains). The least busy section is directly to the north, Bengbu–Nanjing (58 southbound trains). That's still significantly less than the busiest section in France and I guess Europe (the LGV Sud-Est between the junction outside Paris and the junction for Dijon; about 125 trains per day per direction), but trains are higher-capacity.

_{*Lunatic*, n.
One whose delusions are out of fashion.}