Stacked observed infrared-excess (IRX) 3-σ limits as a function of stellar mass (M_⋆). For each M_⋆ bin, the weighted median IRX upper limit is shown (same colors and markers as in Fig. 15). Results are separated into three photometric redshift bins, all of which are upper limits. We also show a number of previously reported IRX–M_⋆ relations (Consensus, F17, M18, B16 and H14) and the locations of three well-known local star-forming galaxies (M 82, NGC 7552 and NGC 7714). Downward arrows have 1-σ length. Horizontal errorbars indicate the 16th and 84th percentiles of the distribution of LBG candidates for each M_⋆ bin. Yellow crosses show the two individual ALMA detections.