Notes. Median dense gas ratios across the combined literature sample presented in Fig. 2, including ALMOND and EMPIRE, and for respective subsamples, including clouds and clumps and resolved and integrated galaxy surveys. The values across the ‘Parts of Galaxies’ studies are computed from unique targets (i.e. Bigiel et al. 2015; Kepley et al. 2014; Jiménez-Donaire et al. 2019; Sánchez-García et al. 2022; Neumann et al. 2023a; Bešlić et al. 2024), to avoid target duplication). The ‘Combined’ measurements are computed from the medians of each respective study. ‘ALMOND & EMPIRE’ results were obtained from the medians of each respective galaxy (i.e. from 31 galaxies) and consider non-detections (in contrast to the other columns, which only consider 3-sigma detected data). All values are on a logarithmic scale. Columns 2 and 3 list the 16th percentiles, medians, and 84th percentiles of log₁₀ SFR/HCN and log₁₀ IR/HCN. Column 4 displays the dense gas depletion time (${\tau }_{\mathrm{dep}}^{\mathrm{dense}}$) in units of years, and Col. 5 the 1-sigma scatter (σ) of the detected HCN data around the median value in units of dex. See Appendix B for details of the compilation.