suggestive of a sharp decline in the number density of pBzK galaxies towards lower luminosities, consistent with expectation from downsizing. As correctly pointed out in [@Grazian_etal:2007] and predicted by [@Daddi_etal:2004], this is not necessarily equivalent to a true decline in the number density of passive galaxies, since the efficiency and completeness of the pBzK technique is largely untested at such faint magnitudes. In particular, there is some evidence that passive galaxies can also be found among the redder sBzK galaxies (at large values of $z-K$), with a possible incompleteness as high as $34\%$ [@Grazian_etal:2007]. We find that randomly adding an additional $34$% of galaxies to the pBzK sample from this part of the diagram is indeed sufficient to remove the apparent turn-over, since these are predominantly the fainter sBzK galaxies.

The sBzK number counts are significantly higher than those of K06, [@Blanc_etal:2008] and [@Imai_etal:2008] (not plotted); while the pBzK number counts are lower. The UDS field is more than 6 times larger than that of the K20 survey and 4 times larger than the one used in [@Imai_etal:2008]. The combined field used in [@Blanc_etal:2008] is of a similar size to the UDS, cosmic variance is the most likely explanation for 