We also plot the z-scores for the cyclometallated ring sizes of the catalysts in Fig. of the SI. These refer to the number of atoms in each of the two cyclic rings that are formed by the metal center and the ligand atoms. For instance, in Fig. (a), the two rings are comprised of Ir -C -C -O -P atoms, and have an identical size of 5-5. Across all pincer complexes reported in literature, symmetric ring sizes for pincer complexes largely outnumber non-symmetric ones. However, the plot indicates that non-symmetric ring sizes are also strongly correlated to ∆G. Similar to the z-scores for building blocks, we see a flipping of the cyclometallated ring sizes from the red zone to the green zone, and vice versa, as we move further through the reaction steps.