ρ_gas as a function of redshift. The green dotted lines represent the total ρ_gas inferred from this work (i.e. integrating the stellar mass function down to 3 × 10⁹ M_⊙) using M_gas deduced with the Scoville et al. (2016) method only. The red and blue dotted lines represent the contribution to the total ρ_gas of galaxies with log₁₀(M_⋆)> 10 and log₁₀(M_⋆)< 10, respectively. The corresponding result deduced throughout this paper are displayed in faded solid red, blue and green coloured lines. The purple and cyan lines represent ρ_gas deduced from the M_gas definition of Wang et al. (2022) and Tacconi et al. (2018), respectively.