X-ray photon count ratio between the XRB and the hot gas component including all galaxies in our sample. Colors represent the component and line styles the energy range in the observed frame. The label “XRB” shows the sum of HMXB and LMXB emission. Top: differential fraction of galaxies with a given count ratio, r. Bottom: cumulative fraction of galaxies. Here, a ratio of r ≥ 2 means that the XRB component is dominant. Ratios exceeding the given range are collected in the last bin.