Characterizing the temporal changes between Hi-C and AIA. Ratio of intensities of AIA and comparable Hi-C convolved and binned (Hi-C [CB]) images, spatially averaged over the field of interest (FOI). 1σ standard errors are marked as vertical bars, and the dark grey shaded region represents the error envelope. The ratios are calculated at the time epochs of the AIA observations (time stamps marked in light grey along the abscissa), using the Hi-C observation nearest in time to it. A systematic decrease of ≈ 8% over the duration of the Hi-C observation is clearly visible in the data.