Radial profiles of the enrichment factor E of Ar, CO, CO₂, and CH₄ in solids relative to their starting abundances as a function of heliocentric distance in the PSN at four epochs (10⁴, 10⁵, 10⁶, and 3 × 10⁶ yr). Rows correspond to Ar, CO, CO₂, and CH₄, while columns capture the temporal evolution of the disk. The orange curve denotes the vapor contribution to the volatile budget, whereas the solid component is divided into pure condensates (blue) and clathrates (green).