Heterogeneous Returns and Wealth Tax Neutrality: A Fokker-Planck Framework
Abstract
We extend the Fokker-Planck framework of Froseth (2026, arXiv:2603.05283) to populations of investors with heterogeneous, persistent return-generating ability. When the drift coefficient in the Langevin equation for log-wealth varies across investors, the proportional wealth tax remains a uniform drift shift but ceases to be neutral in the economic sense: its real incidence differs across ability types, and the stationary wealth distribution changes shape. We derive the extended Fokker-Planck equation on the joint space of log-wealth and ability, characterise the conditions under which the drift-shift symmetry breaks, and identify the consequences for asset prices and portfolio allocations. The analysis connects the neutrality results of Froseth (2026, arXiv:2603.05264) and the Fokker-Planck dynamics of Froseth (2026, arXiv:2603.05283) to the heterogeneous-returns literature, notably the "use-it-or-lose-it" mechanism of Guvenen, Kambourov, Kuruscu, Ocampo-Diaz and Chen (2023).
Cite
@article{arxiv.2603.16006,
title = {Heterogeneous Returns and Wealth Tax Neutrality: A Fokker-Planck Framework},
author = {Anders G Frøseth},
journal= {arXiv preprint arXiv:2603.16006},
year = {2026}
}
Comments
24 pages, 1 figure, 1 table. v2: four Fagereng imprecisions corrected; gross wealth correction; Bernard et al. alpha_eff remark added; phi decomposition formalised; abstract synced