Averaged Alfvén velocity against density from runs M01, M04, M08, M12, and M04A, in blue, orange, green, red, and purple. The same time step as in Fig. 4 and plotted with line width that decreases with increasing in time. Log standard deviations are shown with shades. The thermal sound speed is plotted in black for comparison. The relations v_A ∝ n^1/6 (dashed), v_A ∝ n^−1/2 (plain), v_A ∝ n⁰ (dotted), and v_A ∝ n^0.33 (dot-dashed) are plotted for reference.