In 2019, Chibani et al. used the Materials Project elastic data in order to perform a systematic exploration of the elastic properties (bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and linear compressibility) of inorganic solids. Beyond being able to establish general trends relating these various elastic moduli, the authors could perform tensorial analysis to analyze statistically the importance of elastic anisotropy among more than 10,000 crystals -an order of magnitude that had not been achievable before. Through this analysis, depicted in Figure , they could also quantify some mechanical properties that are often considered by researchers as "rare", but without statistical evidence. Negative linear compressibility (NLC), for example, was found to occur in 3% of the crystalline structures in the database. For negative Poisson's ratio (auxeticity), results are a mixed bag: 30% of materials in the database exhibit a negative Poisson's ratio in a least one direction of space, meaning that the occurrence of partial auxeticity is not a rare phenomenon. On the other hand, materials who exhibit auxeticity in all directions of space (complete auxeticity) are very rare: they account for only 0.3% of the database.