$p_\mathrm{T}$-integrated yield ratios to protons or charged pions (particles + antiparticles) as a function of $\langle {\rm d}N_{\rm{ch}}/\rm{d}\eta\rangle$ measured in $|\eta| 0.5$ in pp collisions~, p--Pb collisions~ and Pb--Pb collisions~ for nuclei (left) and for $\rm{D}^{0}$ and $\rm{J}/\psi$ mesons (right). All yields are obtained at midrapidity, i.e.\,$|y|0.5$. The error bars show the statistical uncertainty, whereas the empty and dark-shaded boxes show the total systematicuncertainty and the contribution uncorrelated across multiplicity bins, respectively.