Luminosity function (upper panel) and the source density evolution (lower panel) are shown for the range of blazar population models tested. The reference models are shown by solid curves, and the shaded regions indicate the bounds of the extreme models. The density evolution can be compared to Fig. 11 in Ajello et al. (2014), although their results are for a ‘luminosity-dependent density evolution’, and so should not be expected to be exactly the same as our simpler model.