(Left panel): The centrality dependence of $\delta_1$, $\delta_2$, $\delta_3$, and $\delta_4$ for pairs of particles of opposite (OS) and same (SS) sign measured in Pb--Pb collisions at $\sqrt{s_\mathrm{{\rm NN}}} = 5.02$ TeV. (Right panel): The charge-dependent differences, $\Delta \delta_{\mathrm{n}}$ for $n$ = 1, 2, 3 and 4, as a function of collision centrality. The statistical uncertainties for some data points are smaller than the marker size. The systematic uncertainties of each data point are represented by the shaded boxes.