$\langle T_{\rm AA} \rangle$-scaled yield of muons from W$^-$ (left) and W$^+$ (right) decays in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV for muons with $\pt^\mu > 10$ GeV/$c$ and $2.5 < y^\mu_{\rm cms} < 4.0$. In the top panels the yield is compared with pQCD calculations using the CT14 PDF  as baseline and implementing the EPPS16  nuclear modifications. The ratio to theory of the measured yield normalised with $\langle T_{\rm AA} \rangle$ evaluated with $\sigma^{\rm inel}_{\rm NN}$ = 67.6 mb and 47.5 mb is shown in the middle and bottom panels, respectively (see the text for details). The horizontal bars indicate the width of the centrality intervals, the vertical bars and boxes correspond to the statistical and systematic uncertainties, respectively. The band indicate the uncertainty on the theoretical computations.