Comparison between the experimental data and the various theoretical predictions for the hydrogen principal Hugoniot. The initial state is taken as ρ₀ = 0.085 g cm⁻³ and T = 20 K. EOS-0.2 and EOS-0.8 are principal Hugoniots obtained with an interpolation range between the SCVH and ab initio data extending from 0.05 g cm⁻³ to, respectively, 0.2 g cm⁻³ and 0.8 g cm⁻³. The former corresponds to the Chabrier et al. (2019) EOS and is thus labeled CMS19-EOS-0.2 in the figure.