Total proper motions against parallax for the sample of stars except for those labeled “unreliable astrometry” (see Sect. 2.3). The 2σ boundaries of the distribution are shown as a rectangle. Empty colored circles show outliers of the distribution of any of the two quantities, and the associated uncertainties are overplotted. The mean and standard deviation obtained from the stars within the 2σ box are shown in the top right corner.