X-ray luminosity distribution in the 2–10 keV energy band for the FERO sample. This sample has been split into Seyfert galaxies (Sy; 82 sources), quasars (QSO; 67 sources), narrow line (NL; 30 sources) and broad line (BL; 60 sources). The shaded area corresponds to the luminosity of those sources within the flux-limited sample for which a significant relativistic broad Fe K_α line detection has been found. The numbers shown on the right in each panel are the median values of the correspondent distribution, also marked by the vertical dashed line.