Capability of the classical trajectory calculation on a potential energy surface (PES) constructed by interpolation in reproducing experimental energy partitioning data has been tested. The title reaction, a prototype polyatomic dissociation which has been heavily investigated over the years, has been taken as the example. The product energy partitioning data obtained by scaling the classical trajectory results on PESs constructed at the moderately high quantum chemical levels of Hartree-Fock (HF), second-order Moller-Plesset (MP2), quadratic configuration interaction single double (QCISD), and B3LYP were nearly level-independent and reproduced the experimental data almost quantitatively. The overall scheme, which is systematic, may become an important quantitative tool for the study of the exit channel dynamics in favorable cases.