Evolution of the AGN bolometric luminosity density: the red band has been computed from a compilation of X-ray luminosity functions integrated in the range log L_X = 42−45, se text for details, and assuming the Marconi et al. (2004) bolometric correction; the blue solid line is the Aird et al. (2015) determination. Fort the UV luminosity density the cyan band is the average of a compilation from Santini et al. (2009), Gruppioni et al. (2015), Bouwens et al. (2011; 2015). The black solid line is the Madau & Dickinson (2014) determination.