Upper panel: redshift distribution of the whole CANDELS sample in the COSMOS field, taken from Nayyeri et al. (2017, N17, gray filled histogram). We also identify the N17 objects that do not have a counterpart (within 0.8″) in the COSMOS2015 catalogue, showing their N(z) with a red histogram. Middle panel: ratio between the CANDELS objects with a match in COSMOS2015 (N_matched) and all the CANDELS entries (N_tot) in bins of [3.6] mag (filled circles). These estimates are divided into three redshift bins in the range 2.5 <z_phot,N17< 6 (see colour-code inset); a dashed line marks the 70% completeness. Lower panel: similar to the middle panel, but the N_matched/N_tot ratio is estimated to reproduce the sensitivity depth of UltraVISTA-Deep.