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Energy differences between frozen core and all electrons correlated.
MP2, MP3, MP4, B2PLYP, CCSD, and CCSD(T)

For Ne2 (Neon diatomic)

Energies in Hartree
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
Moller Plesset perturbation MP2=FULL 0.000000 -0.003728 -0.003728 -0.001813 -0.002918 -0.002918 -0.003715 -0.037842 -0.037842 -0.006704 -0.004088 -0.025941 -0.065374 -0.004387 -0.026857 -0.065548
MP3=FULL         -0.002539   -0.032024                  
Coupled Cluster CCSD(T)=FULL         -0.002606           -0.003714 -0.025357 -0.066146 -0.004013 -0.026308 -0.066310
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ