The ratio between $R_{\mathrm{PbPb}}$ for inclusive $\jpsi$ at forward rapidity and the product $R_{\mathrm{pPb}} \times R_{\mathrm{Pbp}}$ of the nuclear modification factors at forward and backward rapidity. None of the uncertainties cancels out in the ratio. Statistical uncertainties are shown as vertical error bars, while the boxes around the points represent a quadratic combination of uncorrelated and partially correlated systematic uncertainties. The box around $S_{\rm J/\psi}=1$ corresponds to correlated uncertainties The horizontal bars coincide with the widths of the $\pt$ bins.