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3362As an important component of operating costs, excessive social security contribution reduces the willingness and contribution rate of small- and medium-sized firms. In China, one third of firms do not participate in social security, and the other firms generally have the problem of evasion and arrears. Specifically, Feng (2013) finds that the contribution rate of Chinese industrial firms is uneven, and the average rate is only 10.82%, far lower than the legal rate. How to explain the variation in social security contribution rate among firms? Is social security contribution the burden of business activities? Answering these questions helps to understand the motivation of firms’ social security contribution, bolster up the design of social security collection system, and provide theoretical and practical reference for the “cost reduction” of supply-side structural reform.
This paper investigates the relationship between labor market size (LMS) and firms’ social security contribution rate (SSCR) based on the profit maximization framework. Given the dual effects of SSCR on firms’ labor productivity and financial distress cost, optimal SSCR is achieved when marginal income equals to marginal cost. As LMS expands, decreasing search cost and compensating differentials for job loss risk increase optimal SSCR. Further, the empirical results measuring LMS by industrial employment capacity find that LMS significantly increases firms’ SSCR belonging to the same industry, especially for firms with serious financial constraints, high unemployment cost and private ownership. In addition, increasing SSCR significantly deteriorates firms’ performance, suggesting that the cost effect plays a leading role.
Our findings demonstrate that the behaviors of social security by firms are subject to industrial environment, suggesting that it is necessary to account for the issue when policymakers adjust economic policies. Our paper contributes to the literature in three aspects: First, from the perspective of endogenous social security contribution, we explore the impact of labor market size on firms’ social security contribution, which enriches the labor “thick market” theory and relevant literature of firms’ social security contribution. Second, we build a theoretical framework to explain the endogenous logic of labor market size affecting firms’ social security contribution. Third, understanding the logic of firms’ social security contribution provides a micro basis for the reform of social security collection and contribution system.
