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Even though the MIP peaks are quite stable, there is still a possibility that since the MIP peaks are pedestal subtracted, downward trending pedestals could mask degrading tiles. However, the pedestals are also very stable (much more stable than the MIP peaks in fact), thus indicating that this is not the case. Below are histograms of the Pedestals (The left is in units of fraction of the pedestal per year, the right in raw PHA per yeayear).
