As shown in Figure , we found that the point estimate for the slope of HF/6-31G* dipole moments relative to experimental gas phase dipole moments is 1.086 with a 95% confidence interval (CI) of [1.043, 1.124]. In other words, these HF/6-31G* dipole moments are -on average -expected to be somewhere between 4.3-12.4% larger than experimental gas phase dipole moments. Figure , which focuses on molecules with experimental dipole moments below 2.5 D, reveals that there is considerable variation about the regression line, suggesting that there is a large variability in the predicted overpolarization of the HF/6-31G* combination. The HF/aug-cc-pV(T+d)Z combination yields dipole moments that are 1.100 times larger (95% CI: [1.067, 1.123]) (Figure ). This is a somewhat smaller CI than the one obtained for HF/6-31G*, indicating that HF/aug-cc-pV(T+d)Z likely yields more precise predictions of this overpolarization (Figure ). Nonetheless, both the HF/6-31G* and HF/aug-cc-pV(T+d)Z combinations yield point estimates for the characteristic overpolarization of ~10% relative to experimental gas phase measurements, suggesting that this is the amount of overpolarization inherent to the HF method itself.