Distributions of proper motions (top panel) and tangential velocities (bottom panel) of known NYMGs in the heliocentric equatorial coordinate system (left panel) and the LSR equatorial coordinate (right panel). The black and grey filled ellipses on the right panels show how much the whole sample can be shifted due to respectively 1-σ and 2-σ uncertainties on the measurement of the LSR motion relative to the Sun, i.e. errors from Schönrich et al. (2010).