SED-derived DTM ratio, DTM_SED = log A_V − (log N_HI + [M/H]_tot) (top), and depletion-derived DTM_mass ratio (bottom) as a function of dust-corrected metallicity [M/H]_tot. The symbol notation follows Fig. 3. Median relations at five discrete redshifts are also shown from the L-Galaxies MM simulation (Yates et al., in prep.). We observe a potential anticorrelation of DTM_SED with metallicity and a stronger, positive correlation of DTM_mass with increasing metallicity.