Heterogeneous unit labor costs and profit margins in an economy with vintage capital: an amended neo-Kaleckian model

Post-Keynesian literature studying the impact of functional income distribution on economic activity and growth focuses on indirect demand effects (i.e., the consequences of real wage changes on aggregate demand components). The purpose of this article is to explore two points neglected by this literature. First, it ignores the direct supply effects corresponding to the impact of real wage changes on firms’ current profitability. Second, it does not explicitly take into account capital heterogeneity as a consequence of embodied technical progress. We, therefore, analyze the properties of a neo-Kaleckian model that includes both labor productivity differences between firms and the necessary condition of positive profits to engage in production. We show that the positive impact of real-wage increases on effective demand forces some firms to stop production because they become unprofitable. Moreover, the increase in effective demand can be impeded by the decrease in the capacity of profitable firms. Therefore, a recovery of economic activity through wage increases reaches its limits when profitable firms are at full capacity. The model also highlights the importance of technical competition and its role in firms’ behavior regarding capital replacement.