Astrometric reconstruction of the jet structure. The ellipses are contours of the Gaussians with the parameters given in Table 7. These parameters are the epoch-average of the model-fitting results (Table 1) for different time ranges: a) up to June 1997; b) June 1997 through June 2001; c) from June 2001 onwards; and d) all epochs; in a)–d) the contours shown correspond to 0.5 times the FWHM; e) is equivalent to d), but the contours shown correspond to the FWHM. The coordinate origin in each figure corresponds to the centroid of the Gaussian at 5 GHz in b).