747SP numbers vs operators

[Asturias56]

"The large anti-shock bodies on the upper trailing edge of the wings, to increase the critical Mach by reducing transonic drag. The inboard shock bodies, which were larger, were also used for additional fuel tankage"

Don't think it was anything to do with the area-rule although they are associated with it

they were invented by Whitcomb & Kuchemann https://en.wikipedia.org/wiki/Anti-shock_body

"he extension beyond the trailing edge was considered secondary to the body on the wing surface, which slowed the supersonic flow to give a weaker shock and acted as a fence to prevent outward flow. The extension was only long enough to prevent flow separation.[5]: 52  Whitcomb stated that the anti-shock body was no longer required on the top surface of a wing when the supercritical airfoil was introduced[8] because they both decreased the strength of, or eliminated, the shock and its attendant drag."

Generally thought to only give a modest effect overall