Absolute distribution of azimuthal velocities, v_Φ, for stars in eight regions shown in Fig. 6 (see Sect. 3.2). In all panels: velocities are in units of 100 km s⁻¹, and the solid coloured lines correspond to the medians of the distributions. In Regions 1 and 2, the solid purple and red lines correspond to the medians of the v_Φ distributions in Regions 3 and 5, respectively. The number of stars in each region is provided in the upper-left corner of each panel. The 1σ uncertainties (coloured, shaded regions) have been estimated by taking into account both the statistical uncertainty, through 1000 bootstrapped realisations, and the individual uncertainties propagated from the observables.