Evolution of L_z − L_⊥ over time in the McMillan (2017) potential with various values of the flattening, q (in the density), of the halo component. The first column shows the present-day observed distribution in L_z − L_⊥, the second column the stars in L_z − L_⊥ space after ∼2 Gyr integration time, and the third column after ∼10 Gyr. The first row shows the results for the model with the lowest q (0.9) and the bottom row the highest q, with the best estimate, q = 1.2, shown in the middle row.