Aggregate Demand Externalities, Income Distribution, and Wealth Inequality

By Luke Petach, Daniele Tavani

PKES Working Paper 2108

June 2021, revised November 2021

We study a two-class model of growth and the distribution of income and wealth at the intersection of contemporary work in classical political economy and post-Keynesian economics. The key insight is that aggregate demand is an externality for individual firms: this generates a strategic complementarity in production and results in equilibrium underutilization of the economy’s productive capacity, as well as hysteresis in real output. Underutilization also affects the functional distribution of income and the distribution of wealth: both the wage share and the workers’ wealth share would be higher at full capacity. Consequently, fiscal allocation policy that achieves full utilization also attains a higher labor share and a more equitable distribution of wealth; while demand shocks have permanent level effects. Extensions look at hysteresis in the employment rate and growth. These findings are useful as an organizing framework for thinking through the lackluster economic record of the so-called Neoliberal era, the sluggish recovery of most advanced economies following the Great Recession, and the importance of fiscal policy in countering large shocks such as the Covid-19 pandemic.

Keywords: Externalities, Capacity Utilization, Factor Shares, Wealth Inequality

JEL classification: D31 D33 D62 E12