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As is apparent from the plots, the MIP peaks are quite stable, to within about 5 percent of a MIP per year. The is no indication of any systematic degrading. The Gaussian distribution of the trends even suggests that the appearance that some individual tiles are trending down is more likely due to noise than to any degrading of particular tiles. The mean of the trends is even slightly positive. The only possible systematic effect is demonstrated by the red bars on both plots. These bars are the data from the eight PMT's attached to the four large bottom tiles on the sides. As can be seen, all eight of these PMT's are trending downward. Due to their larger size, these tiles may be degrading more quickly than the others. However, this degrading is again at it's maximum