Here, the dataset begins to reflect the true degree of imbalance in the literature data (Figure ). This can be attributed to human propensity for round numbers, as well as picking the most convenient option. For example, although the D:A ratio is incredibly easy to vary, the most common values are 1 and 0.5 (i.e., 1:2 D:A). Similarly, only three solvents (CF, CB, o-DCB) and only two solvent additives (CN, DIO) make up the vast majority of entries. Consequently, relatively little of the solvent property space has been sampled (Figures and).