The ESDs defined by Eq. 14 and Eq. 13 are in good agreement with the numerically derived ESDs 10 over the whole range of α (Fig. ). We will therefore update the ESD definitions for both the Generalised Debye and SEF models in CC-FIT2 10 to those described Table : Parameters obtained from fitting relaxation rates obtained from AC susceptibility measurements along with those extracted from Waveform or DC decay measurements performed here to Eq. 10. The resultant fits are shown graphically in Fig. (Fig. ). The exception is at 2 K, where the ESDs for the waveform data are narrower than for the decay-derived data and the other waveform data at higher temperatures -this is attributed to noise in some of the 2 K waveform datasets. suggests that only a Raman relaxation mechanism is active at low temperature owing to the linearity of the plot (Fig. and Ref. ). However, the waveform τ Debye -1 and decay e ⟨ln [τ]⟩ rates show a levelling off at low temperature, suggesting the presence of QTM, consistent with the hysteresis data. Fitting the temperature-dependence of τ Debye -1 or e ⟨ln [τ]⟩ to Eq. 10 gives chemically sensible parameters (Figs. 5 and S110, Table ), including a Raman exponent of ca. 4 compared to the originally-reported unphysical value of ca. 1. Low β values will lead to the largest deviation between τ * and e ⟨ln ). However, using reported τ * and β val- and M eq were allowed to vary freely in fitting. Using the reported parameters, e ⟨ln [τ]⟩ = 10 4.20(0.67) s (4.4 hrs) but refitting the experimental data with M 0 fixed to the first point measured at zero-field and M eq = 0 (Fig. and Fig. ) gives e ⟨ln [τ]⟩ = 10 4.29(0.62) s (5.4 hrs). A necessary step in progressing towards chemical control of QTM is the accurate determination of relaxation times and these large variations stress the need for consistency in fitting and interpretation of magnetisation decays. The changes to how one should analyse AC susceptibility, waveform and DC decay data will be updated into CC-FIT2. We also strongly encourage the SMM community to publish their full magnetic datasets, to enable re-analysis of magnetisation decay data.