商业银行债券融资与货币政策传导

Commercial Bank Bond Financing and Monetary Policy Transmission

本文基于我国监管政策和金融机构异质性特征,通过构建理论模型论证了银行债券融资能力提升将产生以下效果:第一,使中小银行能够通过同业交易渠道,向大型银行借取更多低成本资金。第二,提高了银行向非银行部门主动融资的能力,从而降低银行的流动性管理需求,并向非银行金融机构供应更多抵押资产。第三,提高单个银行利用整个银行系统的信贷资产价值来补充资本的能力。这些效应共同降低了中小银行的资金成本、准备金抵押品成本和资本成本,以及整个银行系统的流动性监管引致成本,同时还向市场提供了更多优质抵押品,最终会提高货币政策影响各类信贷规模的能力,并降低银行异质性和资本消耗率对信贷结构的扭曲程度。但同时,这些效应也会因改变银行的信贷偏好而产生新的扭曲效应,并且还会提高金融机构间的债务互联性,因此会增加一些新的宏观金融风险问题。

Since 2014,Chinese commercial banks have been increasingly active in issuing bonds(including interbank certificates of deposit)for financing,which is reflected,first,in a considerable increase in the proportion of bank bond liabilities to total liabilities and,second,in the considerable share of bank bonds and interbank certificates of deposit in China's asset market.In this context,we focus on two important issues.First,we examine why there are large-scale commercial bank bond financing transactions in China,examining the structural characteristics of the Chinese financial market and the financing motivations of financial institutions underlying these transactions.Second,we analyze the impact that improving banks'bond financing capabilities has on policy effectiveness,especially the effects of monetary policy(encompassing both scale and structural effects),which are closely related to the banking system.The literature mainly explores the active financing behavior of banks from the perspective of credit asset securitization,and does not accurately depict the characteristics of bond financing.Furthermore,it does not provide a detailed description of China's financial market and regulatory policy characteristics,and is thus unable to provide complete answers to the above issues.The research in this article begins with the structure of China's financial market,financial regulatory policies,and the characteristics of bond liabilities,analyzing the motivation of bond financing transactions of Chinese commercial banks,and the impact of bank bond financing capacity on the transmission effect of monetary policy.Specifically,the core setting of the theoretical model in this article reflects the following characteristics of and facts regarding China.First,the setting reflects the heterogeneity of financial institutions in China.China's small and medium-sized banks have higher deposit costs and require more high-quality collateral assets to obtain reserves than large banks,whereas the fund sector can use both sovereign bonds and bank bonds to meet collateral needs.The second characteristic is the constraints imposed by macro prudential regulation on bank credit.The banking system is required to reserve a certain proportion of sovereign bonds as liquid assets for deposit liabilities to meet liquidity regulatory needs.Small and medium-sized banks often face capital constraints and are unable to allocate more credit lines to mortgage loans,which have lower risk weights than other loans.The third characteristic is that bond liabilities have a higher degree of marketization pricing than deposit liabilities,and differ from deposit liabilities in terms of debt stability and underlying assets.Therefore,bond liabilities have the advantage that banks do not need to pay reserves and liquidity management costs.Furthermore,some bank bonds have the attribute of subordinated bonds and can be used as capital to absorb risk losses under certain conditions.The literature on the Chinese financial sector,the main theoretical source of this article,comprehensively confirms the above-mentioned heterogeneity of financial institutions and the characteristics of regulatory policies.The results of the model developed for this study indicate that the basic trading structure and motivation for using bank bonds are as follows.First,the deposit interest rates and collateral costs of large banks are lower than those of small and medium-sized banks;thus,large banks are naturally willing to allocate more low-cost capital to them by purchasing small and medium-sized bank bonds.Second,to improve their credit rating and expand their bond issuance quotas,small and medium-sized banks facing capital constraints may supplement their capital by issuing subordinated bonds,or even purchasing the ordinary bonds of large banks,but at the cost of experiencing financial losses.Third,the fund sector is willing to purchase two types of bank bonds to meet collateral needs.Under this transaction structure,we find that improving banks'bond financing capacity directly reduces the capital cost and the reserve borrowing and lending collateral costs of small and medium-sized banks.It can also reduce the liquidity supervision cost by saving treasury bonds(reducing the premium on treasury bonds)and the quasi out statement effect;that is,the transactions involving banks selling bank bonds to the fund sector can directly reduce the liquidity supervision demands of the banking system.In addition,more collateral is provided to the fund sector.These effects greatly alleviate the“liquidity,funding,and interest rate constraints”of monetary policy transmission that the People's Bank of China raises as issues of concern,ultimately enhancing the ability of monetary policy to affect the credit scale of financial institutions,especially small and medium-sized banks and fund departments.Indeed,small and medium-sized financial institutions are constrained by capital and collateral costs as a result of improving the financing capacity of bank bonds.The main conclusion and policy implications of this article are that improving the financing capacity of bank bonds can improve the transmission effect of monetary policy in terms of both the scale and comprehensiveness of credit provision,which is valuable in the context of promoting China's stable growth and structural adjustment policies.However,simultaneously,it increase banks'preferences for low-risk mortgage loans to serve as underlying assets for the bonds,leading to new credit structure distortion effects.It may also weaken the financial system's resilience to shocks by enhancing debt interconnectivity between banks.