Average normalised anisotropy in the outer regions (>2r_hl) using only Gaia proper motions, without removing the contribution by rotation. Top panel: the correlation with the cumulative radial distribution parameter $A_4^{+}$ (Leitinger et al. 2023), and bottom panel: the correlation against the z-component of the angular momentum, where positive (negative) values indicate retrograde (prograde) orbits. Clusters are colour-coded by their progenitor structures, as classified by Massari et al. (2019). M-D: main disc of the Milky Way progenitor, L-E: unassociated low-energy group, H-E: high-energy unassociated group, H99: Helmi streams, G-E: Gaia-Enceladus, Seq: Sequoia. Each panel also shows the Spearman and Pearson rank correlation coefficients for each parameter, with corresponding log p-values to show the significance of the correlations (log(p) ≤ −1.3 indicates a p-value ≤0.05, meaning the correlation is statistically significant and not likely to be the result of random chance).