Normalised distributions of AGN power, both radiative (L_rad,AGN) and mechanical (L_mech,AGN) as a function of redshift. The distributions of L_rad,AGN are shown for HLAGN (blue) and HLAGN with radio excess (blue thicker), while the distributions of L_mech,AGN are shown only for MLAGN (orange) and HLAGN with radio excess (orange thicker). The median value of each distribution is indicated with a vertical line with same colour and thickness of the corresponding histogram. The orange horizontal lines around the median value of the AGN mechanical power show the range within which the median could shift if accounting for all of the uncertainties on the L_{1.4 GHz}–L_mech,AGN relation (see text for details). The normalisations are set separately for the two L_mech,AGN (red) and the two L_rad,AGN (blue) distributions. See the text for details.