Three parameters of the primary power law plotted against the flux of the soft excess (calculated as the 0.3–2 keV flux of the diskbb component, see Section 3.3). Upper panel: primary flux in the 3–10 keV range. Middle panel: primary flux in the 10–50 keV range. Lower panel: primary photon index. All fluxes are in units of erg s⁻¹ cm⁻². The blue solid lines represent the mean value for each parameter, while the blue dashed lines represent the standard deviation. The red lines represent linear fits to the data.