Normalized spectra of the first three significant components (top to bottom) of the Ark 564 between 0.4–9.0 keV. We used the black, red and blue to mark the first, second, and third principle component, respectively. We binned the spectra logarithmically into 65 energy bins and calculated the errors by perturbing the input spectra. The zero level in each panel is marked with a green dashed line. We also show the variability percentage of the component in the top left corner of each panel. For the third component, we do not include the rightmost datapoint (x = 8.6, y = 0.84) to show the detailed structure in the soft energy clearly.