Top: radial velocities of HD 204313 with the corresponding one-Keplerian model. Red points are HARPS data; blue and orange points represent CORALIE07 and CORALIE98 data, respectively; magenta points are the Robertson et al. (2012) McDonald radial velocities. Middle: generalised Lomb-Scargle periodogram of the residuals to the model plotted in the upper panel, exhibiting excess power at P = 34.9 days and a low-frequency trend. The horizontal dotted and dashed lines represent the 10% and 1% p-value levels, respectively. Bottom: GLS periodogram of the RV residuals to the one-Keplerian model without the HARPS data. The peak at 34.9 days is no longer significant, and the long-term trend has been replaced by a definite period at P ~ 3500 days with insignificant power.