Ratio of kinematic membership probabilities of thick to thin disc TD/D of the sample, estimated in Sect. 3.6 following the approach by Bensby et al. (2014) and comparable with their Fig. 1. Most stars are assigned to the thin disc with this criterion. 12 stars, marked as enlarged black dots, are likely to be halo stars, based on their membership ratios with respect to the halo, D_H and TD_H respectively.