This paper provides a novel analytical characterization of the dynamics of a canonical model of lumpy microeconomic adjustment in the presence of aggregate and idiosyncratic shocks. The dynamics of the firm-size distribution are shown to have an intuitive partial-adjustment representation for which the rate of convergence equals the rate of adjustment. Interestingly, analytical approximations nonetheless imply aggregate dynamics that are almost neutral. This neutrality is shown to emerge from a symmetry property in the implied distributional dynamics, and arises even in the absence of general equilibrium adjustment. Quantitative illustrations based on the employment adjustment literature confirm these analytical results.