Following an earlier study to define the intensity-energy calibration of Auger electron spectrometers, this study determines the changes in calibration that occur after two further years of use. Five respondees, using cylindrical mirror analysers from the earlier interlaboratory study, have remeasured spectra for the Cu, Ag and Au reference materials, SCAA 87, under standard conditions. The results show that two of the instruments perform as before with no effective change in calibration, two have 10% lower intensities at energies below 100 eV and one has 100% higher intensities at low energy, when the spectra are all normalised at 1000 eV. These changes arise from ageing of the channel electron multiplier (CEM) detectors and the effects of stray magnetic fields. Calculations are provided to show the improvements in stability achieved by biasing the front of the CEM by +250 V.