Dust-to-stellar mass ratio (left) and gas-to-dust mass ratio (right) as a function of redshift. The red, green, and yellow filled circles show the binned averages as in the left panel in Fig. 8. In the left panel, the blue horizontal dashed line marks the sample median M_dust/M_⋆ ratio of 0.006, while that in the right panel shows the median M_gas/M_dust ratio of 120. The other dashed lines show the linear fits through the binned data points (see text for details).