Per-trigger nuclear modification factor ($I_{\rm{AA}}$) of the NS (left) and AS (right) associated peak yields for electrons from heavy-flavor hadron decays in intervals $4 \pt^{\rm{e}} 7$ \GeVc compared to $7 \pt^{\rm{e}} 16$ \GeVc as a function of $\pt^{\rm{assoc}}$ in central Pb--Pb collisions. The statistical (systematic) uncertainties are shown as vertical lines (empty boxes). In some $\pt^{\rm{assoc}}$ intervals the AS yield is consistent with zero within one standard deviation of total uncertainty. For those intervals, upper limits on the $I_{\rm{AA}}$ for 68\% and 95\% confidence levels are shown with arrows and boxes, respectively.