Histogram of the values of 5000 random catalogues on the sky (each having N_c = 1526), with different colours representing different Planck foreground-cleaned maps. The 68% width of the 2D-ILC, SMICA, NILC, SEVEM and Commander histograms are 2.86, 2.49, 2.48, 2.53, 2.62 (×10⁻⁷), respectively. The vertical lines represent the average ΔT/T values at true MCXC cluster positions for each map. One can see that only for the 2D-ILC map is this value within the 68% range of the random catalogue distribution, while others are quite far off. This indicates that, except for the 2D-ILC map, the public Planck maps have residual tSZ contamination at the cluster positions.