Total dust-corrected metallicity [M/H]_tot evolution with redshift 𝓏 for QSO-DLAs (black triangles) and GRB-DLAs (orange diamonds). The larger points (purple for QSO-DLAs and green for GRB-DLAs) show the HI-weighted mean metallicities binned in redshift and the lines are their corresponding linear fits. The open symbols at redshift 𝓏 = 0 refer to the Milky Way (green), the LMC (purple), and the SMC (blue). The dotted line shows the solar metallicity ([M/H]_tot = 0).