ATCA frequencies. Estimated uncertainties represent a combination of random noise and scale errors resulting from errors in the calibration. Except at 8.6 GHz, the scale errors are estimated from the scatter in the measured flux densities of J0536-6918 since day 4000. At 8.6 GHz, J0536-6918 is outside the half-power radius of the primary beam, and scale errors are taken to be 1.25 times the 4790 MHz scale errors. At the lower frequencies and at later times, the errors in the flux density estimations are dominated by the scale errors. Since, except at 8.6 GHz, the flux density of J0536-6918 is comparable to that of SNR 1987A and since there is no evidence for systematic changes in the flux density of J0536-6918, these scale errors can be reduced by dividing the flux densities by the normalised flux density of J0536-6918 from the same observation. Flux densities from day 3000 scaled in this way for 1.4, 2.4 and 4.8 GHz are shown in Figure \[fg:scflux\].

These plots show that the continued increase in flux density observed at 843 MHz by Ball et al. (2001) is also observed at higher frequencies. The increase in slope observed at about day 2900 in the MOST 