差别化存款保险费率与银行风险承担——基于我国农村银行的经验证据

本文拓展了Freixas and Rochet(2008)的理论模型,证明存款保险差别化费率机制对银行风险承担具有抑制作用,在此基础上选取我国农村银行为研究对象,运用2015—2019年某省119家法人投保机构进行实证检验。研究发现:引入差别化费率设计显著降低了农村银行的风险承担;这一作用存在异质性,对于自身风险承担水平较低、资产规模较大的农村银行来说,抑制作用更为明显。进一步研究发现,差别化费率机制在一定程度上缓和了农信社改制短期内对农商行风险可能造成的不利影响。本文结论对加强存款保险制度的早期纠正功能、防范化解金融风险以及深化农村金融机构改革具有一定的理论意义和参考价值。

Differential Rate Mechanism of Deposit Insurance and Bank Risk-taking: Evidence from China's Rural Banks

Effectively identifying and preventing risks from problem banks and improving financial security and the emergency response mechanism are increasingly important practical problems. As an important part of the financial safety net, the deposit insurance system can play an early-warning role in dynamic supervision and in the disposal of financial risks.
Regarding the effectiveness of the deposit insurance system, the prevailing view is that a poorly designed system increases the risk of a bank crisis. However, an incentive compatible design can weaken the adverse impact of moral hazards. As an important part of the risk-minimization design of the deposit insurance system, a differential rate can effectively reduce moral hazards in banking.
China established its deposit insurance system in 2015. Domestic scholars discuss the positive and negative effects of deposit insurance on China's banking system, emphasizing how it can prevent risk exposure and the response of regional banks and how to coordinate it with other financial reform measures. Considering these practical problems and research backgrounds, this paper theoretically analyzes the inhibitory effect of the differential rate mechanism on bank risk before and after the implementation of the deposit insurance system. By expanding the model of Freixas and Rochet (2008), it is proved that a differential rate, compared with a fixed rate, can inhibit high-risk investment behavior by banks and alleviate moral hazards. Moreover, a differential rate based on risk makes early correction more effective. This paper selects 119 rural banks which have relatively greater potential risks and uses data from 2015 to 2019 to conduct an empirical test.
The main contributions of this paper are as follows. (1) A theoretical extension of the Freixas and Rochet (2008) model is used to deduce and prove the inhibitory effect of differential rates on bank risk-taking. (2) This paper discusses the impact and heterogeneity of the dynamic transition from a unified rate to a differential rate on bank risk-taking after the establishment of China's deposit insurance system, enriching the theoretical discussion. The differential rate mechanism significantly inhibits risk-taking by rural banks in China, and this inhibitory effect is more obvious for banks with less risk and more assets, whereas the effect on country banks is relatively insignificant. (3) This paper not only verifies the impact of a differential rate mechanism on bank risk-taking but also considers the effect of restructuring rural credit cooperatives on a selected sample of rural banks in a similar period. The results show that in the short term, the reform of rural credit cooperatives intensifies risk-taking of rural commercial banks, but the differential rate mechanism alleviates this negative effect to a certain extent.
According to the theoretical analysis and empirical results in this paper, the following policy implications are obtained: First, improving the design of the deposit insurance system can not only weaken the negative impact of the moral hazards inherent in the system but also increase its role in stabilizing the banking system. We should give full play to thePrompt Corrective Action of the deposit insurance system, which include monitoring and timely intervention, improve the effectiveness of the deposit insurance system in disposing of financial risks, reduce the cost of risk disposal and prevent the infection and diffusion of financial risks. Second, we should strengthen the risk early-warning mechanism and dynamic supervision of small and high-risk banks and require rectification when problems are found, to avoid the accumulation of risks.