Lomb-Scargle power of the 625 d period as a function of the number of data points (N). The red squared data points represent the real data while the blue circular data points represent simulated data. Top: growth of the Lomb-Scargle power from 1980–2013. Data points were added in steps of 20 in chronological order. A decrease in statistical power is observable for the real data between N  =  300 and N  =  320. Bottom: growth of the Lomb-Scargle power from 2013–1980. Data points were added in steps of 20 in reversed chronological order. Before N  =  240 (which represent the newest RV data) the ∼620 d period is clearly visible as the growth in power shows the same linear slope as the simulated data. The older RV data (taken before 2006) however cause a decrease in the slope and a drop in power at N = 340.