商业银行资本工具创新及定价研究

资本工具的创新可以拓展银行资本补充渠道和空间,提升银行补充资本的能力,强化银行业的资本约束,增强风险管理水平,推动商业银行业务转型,增强服务实体经济的能力.本文在阐述我国资本工具的应用及创新背景的基础上,通过建立二叉树模型,探讨了我国新型资本工具定价问题并提出相关建议.     

《银行资本充足率监管征求意见稿》的影响研究

2011年5月,银监会下发了融合《巴塞尔协议II》及《巴塞尔协议III》内关于资本计量、管理等内容的《银行资本充足率监管征求意见稿》,这标志着金融危机后我国的新监管标准即将落地。该监管新规将使国有五大行资本充足率下降。五大行可以从补充资本、降低加权风险资产、增强资本管理能力等方面应对监管新规。     

Private equity and regulatory capital

Regulatory capital requirements for European banks have been put forward in the Basel II Capital Framework and subsequently in the capital requirements directive (CRD) of the EU. We provide a detailed discussion of the capital requirements for private equity investments under different approaches. For the internal model approach we present a structural model that we calibrate to a proprietary dataset. We modify the standard Merton structural model to make it applicable in practice and to capture stylized facts of private equity investments. We also implement the early default feature with a fast simulation algorithm. Our results support capital requirements lower than in Basel II, but not as low as in CRD, thereby giving adverse incentives to banks for using advanced risk models. A sensitivity analysis shows that this finding is robust to parameter uncertainty and stress scenarios.     

Capital incentives and adequacy for securitizations

This paper analyzes the capital incentives and adequacy of financial institutions for asset portfolio securitizations. The empirical analysis is based on US securitization rating and impairment data. The paper finds that regulatory capital rules for securitizations may be insufficient to cover implied losses during economic downturns such as the Global Financial Crisis. In addition, the rating process of securitizations provides capital arbitrage incentives for financial institutions and may further reduce regulatory capital requirements. These policy-relevant findings assume that the ratings assigned by rating agencies are correct and can be used to build a test for the ability of Basel capital regulations to cover downturn losses.     

The New Basel Capital Accord: Making it Effective with Stronger Market Discipline

In January 2001 the Basel Committee on Banking Supervision proposed a new capital adequacy framework to respond to deficiencies in the 1988 Capital Accord on credit risk. The main elements or 'pillars' of the proposal are capital requirements based on the internal risk-ratings of individual banks, expanded and active supervision, and information disclosure requirements to enhance market discipline. We discuss the incentive effects of the proposed regulation. In particular, we argue that it provides incentives for banks to develop new ways to evade the intended consequences of the proposed regulation. Supervision alone cannot prevent banks from 'gaming and manipulation' of risk-weights based on internal ratings. Furthermore, the proposed third pillar to enhance market discipline of banks' risk-taking is too weak to achieve its objective. Market discipline can be strengthened by a requirement that banks issue subordinated debt. We propose a first phase for introducing a requirement for large banks to issue subordinated debt as part of the capital requirement.     

试论商业银行法律风险——从《巴塞尔新资本协议》看银行法律风险

巴塞尔银行监管委员会<统一资本计量和资本标准的国际协议:修订框架>,将法律风险纳入了银行资本充足率监管框架,要求银行采用规定的方法计量法律风险,并以此为基础确定其资本标准.本文从法律风险定义人手,论述银行法律风险的分类、成因、特性、表现形式及可控性,提出银行法律风险管理与控制的思路和方法.     

《新资本协议》对商业银行信贷运行的影响——兼论其宏观经济效应

《新资本协议》的出台和实施是银行监管历史上一个具有里程碑意义的事件。本文认为,《新资本协议》特别是内部评级法极大地提高了资本监管的风险敏感度,将对商业银行的信贷增长方式、信贷结构调整和贷款损失准备计提、以及宏观经济运行产生一定的影响。按照目前我国商业银行资本充足水平和资产质量,无论是实施标准法还是内部评级法都将强化信贷扩张的资本约束效应。我国应慎重选择《新资本协议》的实施时机,避免由此对信贷供给和宏观经济运行造成的负面冲击。     

Economic and regulatory capital allocation for revolving retail exposures

We present two internal capital allocation models and compare the capital ratios they generate with those prescribed by the latest revision of Basel’s New Capital Accord proposal for advanced retail portfolios, which allows for explicit future margin income recognition. Given a test portfolio of credit card exposures that we assemble, we find that Basel’s ratios are closer to those generated by our models for low credit risk segments. We attribute the discrepancies to the different ways Basel and our models account for future margin income, to Basel’s assumptions about asset correlations and to one model taking macroeconomic conditions into account.     

Optimal portfolios with minimum capital requirements

We propose a novel approach to active risk management based on the recent Basel II regulations to obtain optimal portfolios with minimum capital requirements. In order to avoid regulatory penalties due to an excessive number of Value-at-Risk (VaR) violations, capital requirements are minimized subject to a given number of violations over the previous trading year. Capital requirements are based on the recent Basel II amendments to account for the ‘stressed’ VaR, that is, the downside risk of the portfolio under extreme adverse market conditions. An empirical application for two portfolios involving different types of assets and alternative stress scenarios demonstrates that the proposed approach delivers an improved balance between capital requirement levels and the number of VaR exceedances. Furthermore, the risk-adjusted performance of the proposed approach is superior to that of minimum-VaR and minimum-stressed VaR portfolios.     

Forecasting bank loans loss-given-default

With the advent of the new Basel Capital Accord, banking organizations are invited to estimate credit risk capital requirements using an internal ratings based approach. In order to be compliant with this approach, institutions must estimate the loss-given-default, the fraction of the credit exposure that is lost if the borrower defaults. This study evaluates the ability of a parametric fractional response regression and a nonparametric regression tree model to forecast bank loan credit losses. The out-of-sample predictive ability of these models is evaluated at several recovery horizons after the default event. The out-of-time predictive ability is also estimated for a recovery horizon of 1 year. The performance of the models is benchmarked against recovery estimates given by historical averages. The results suggest that regression trees are an interesting alternative to parametric models in modeling and forecasting loss-given-default.     

Procyclicality: The Macroeconomic Impact of Risk-Based Capital Requirements

Recent research on the Basel II capital framework suggests that binding capital requirements may be responsible for bank behaviour which causes procyclical amplifications of the macroeconomic cycle. This paper presents a model of the interrelations between the state of the economy, credit risk, and loan supply to clarify and quantify this effect. Special attention is paid to the fact that both regulatory and economic capital requirements can significantly influence loan supply, provided that they are binding. The model shows that both economic capital, based on a one-factor model, and the regulatory IRB requirements cause more procyclicality than the constant regulatory requirements of the Basel I capital accord. However, the overall impact depends on the interrelation of the regulatory requirements with economic capital. Based on this result, the replacement of the Basel I requirements with risk-sensitive IRB capital requirements boosts procyclicality under most, but not under all conditions.     

Effects of the New Basel Capital Accord on Bank Capital Requirements for SMEs

Using data from three countries (US, Italy and Australia) and surveying related studies from several other countries in Europe, we investigate the effects of the New Basel Capital Accord on bank capital requirements for small and medium sized enterprises (SMEs). We find that, for all the countries, banks will have significant benefits, in terms of lower capital requirements, when considering small and medium sized firms as retail customers. But they will be obliged to use the Advanced IRB approach and to manage them on a pooled basis. For SMEs as corporate, however, capital requirements will be slightly greater than under the existing Basel I Capital Accord. We believe that most eligible banks will use a blended approach (considering some SMEs as retail and some as corporate). Through a breakeven analysis, we find that for all of our countries, banking organizations will be obliged to classify as retail at least 20% of their SME portfolio in order to maintain the current capital requirement (8%). JEL classification: G21, G28     

Bank regulation and international financial stability: A case against the 2006 Basel framework for controlling tail risk in trading books

In attempting to promote international financial stability, the Basel Committee on Banking Supervision (2006) provided a framework that sought to control the amount of tail risk that large banks around the world would take in their trading books relative to their corresponding minimum capital requirements. However, many of these banks suffered significant trading losses during the recent financial crisis. Our paper examines whether the Basel framework allowed banks to take substantive tail risk in their trading books without a capital requirement penalty. We find that it allowed banks to do so and that its minimum capital requirements can be notably procyclical. Hence, focusing on the way the Basel framework sought to control the amount of tail risk in trading books relative to their corresponding minimum capital requirements, our paper supports the view that it was not properly designed to promote financial stability. We also discuss alternative regulatory frameworks that would potentially be more effective than the Basel framework in preventing banks from taking substantive tail risk in their trading books without a capital requirement penalty.     

Loan pricing under Basel capital requirements

We analyze the loan pricing implications of the reform of bank capital regulation known as Basel II. We consider a perfectly competitive market for business loans where, as in the model underlying the internal ratings based (IRB) approach of Basel II, a single risk factor explains the correlation in defaults across firms. Our loan pricing equation implies that low risk firms will achieve reductions in their loan rates by borrowing from banks adopting the IRB approach, while high risk firms will avoid increases in their loan rates by borrowing from banks that adopt the less risk-sensitive standardized approach of Basel II. We also show that only a very high social cost of bank failure might justify the proposed IRB capital charges, partly because the net interest income from performing loans is not counted as a buffer against credit losses. A net interest income correction for IRB capital requirements is proposed.     

RAROC AT BANK OF AMERICA: FROM THEORY TO PRACTICE

In 1993, Bank of America's Risk and Capital Analysis Group was charged with the task of developing and instituting a single corporate-wide system to allocate capital to all the bank's activities. Since 1994, that system has been providing quarterly reports of risk-adjusted returns on capital (RAROC) for each of the bank's 37 major business units. By 1995, B of A had also developed the capability to calculate RAROC down to the level of individual products, transactions, and customer relationships. RAROC systems allocate capital for two basic reasons: (1) risk management and (2) performance evaluation. For risk management purposes, the overriding goal of allocating capital to individual business units is to determine the bank's optimal capital structure–the proportion of equity to assets that minimizes the bank's overall cost of funding. This process involves estimating how much the risk (or volatility) of each business unit contributes to the total risk of the bank, and hence to the bank's overall capital requirements. For performance evaluation purposes, RAROC systems assign capital to business units as part of a process of determining the risk-adjusted rate of return and, ultimately, the “economic profit” of each business unit. The objective in this case is to measure a business unit's contribution to shareholder value, and thus to provide a basis for effective planning, capital budgeting, and incentive compensation at the business unit level. Concerns about capital adequacy, along with the Basel risk-based capital requirements, have played some role in the growth of RAROC among commercial banks. But the most powerful impetus to bankers' use of more systematic risk measures is coming from increasingly activist institutional investors. Besides giving senior management an economic basis for evaluating the bank as a portfolio of businesses and for making resource allocation decisions that improve the bank's risk/reward profile, RAROC systems are also expected to produce better performance by holding managers accountable for the amount of investor capital they are putting at risk.     

国有商业银行资本充足监管有效性及其前提条件

资本充足问题一直是各国商业银行外部监管和内部控制共同关心的问题.<巴塞尔协议>出台以来,我国国有商业银行内部激励缺乏,而外部监管又流于形式,资本充足率持续下降.本文从国有悖论、监管宽容和实证推算三个方面重点对国有商业银行资本充足监管的有效性进行分析,认为当前对国有商业银行资本充足监管是无效或低效的.但在我国已经加入WTO的宏观背景下,对国有商业银行进行资本充足监管又是必要和必须的,而前提是对不良贷款进行二次剥离和彻底改制,以建立起现代商业银行制度,从而为国有商业银行资本充足有效监管奠定制度基础.     

Bank Capital Regulation in Contemporary Banking Theory: A Review of the Literature

This paper reviews the theoretical literature on bank capital regulation and analyzes some of the approaches to redesigning the 1988 Basel Accord on capital standards. The paper starts with a review of the literature on the design of the financial system and the existence of banks. It proceeds with a presentation of the market failures that justify banking regulation and an analysis of the mechanisms that have been suggested to deal with these failures. The paper then reviews the theoretical literature on bank capital regulation. This is followed by a brief history of capital regulation since the 1988 Basel Capital Accord and a presentation of both the alternative approaches that have been put forward on setting capital standards and the Basel Committee's proposal for a new capital adequacy framework.     

On the Role of Regulatory Banking Capital

In this paper the authors study the role of regulatory banking capital and analyze the incentive effects of the Basel II Accord. They argue that Basel II may become a source of systemic risk due to endogenous risk and the risk sensitivity of the capital requirements. In this context they note that financial instability may enter via the asset side of the banks' balance sheets when banks are forced to sell assets in order to maintain the capital buffer prescribed by Basel II.     

The Basel Committee proposals for a new capital accord: implications for Italian banks

Following a few general considerations on the recently proposed revision of the Basel Agreement on capital adequacy, this paper focuses on the first pillar of the Basel Committee proposals, the handling of capital requirements for credit risk in the banking book. The Basel Committee envisages an approach alternatively based on external ratings or on internal rating systems for the determination of the minimum capital requirement related to bank loan portfolios. This approach supports a system of capital requirements that is more sensitive to credit risk. On the basis of specific assumptions, these requirements provide a measure of the value at risk (VaR) produced by models used by major international banks. We first address the impact of the standardised and (internal ratings-based) IRB foundation approach using general data on Italian banks loans' portfolios default rates. We then simulate the impact of the proposed new rules on the corporate loan portfolios of Italian banks, using the unique data set of mortality rates recently published by the Bank of Italy. Three main conclusions emerge from the analysis: (i) the standardised approach implicitly penalizes Italian banks in their interbank funding as their rating is generally below AA/Aa, (ii) the average default rate experienced by Italian banks is higher than the one implied in the benchmark risk weight (BRW) proposed by the Basel Committee for the IRB foundation approach, thereby potentially leading to an increase in the regulatory risk weights, and (iii) the risk-weight is based on an average asset correlation that is significantly higher than the one historically recorded within the Italian banks' corporate borrowers. These findings support the need for a significant revision of the basic inputs and assumptions of the Basel proposals. Finally, in relation to the conditions that allow the capital market to effectively discipline banks, we comment on the proposals advanced in relation to the third pillar of the new capital adequacy scheme.     

我国商业银行资本充足率与风险资产关系研究

资本充足率管理是商业银行风险管理的核心。本文构建了反映我国商业银行资本充足率和风险资产关系的模型,对我国商业银行资本充足率和风险资产之间的关系进行分析。结果发现:商业银行资本充足率的变化会引起资本结构的变化,从而对风险资产产生影响。风险资产的变化又会对资本充足率产生影响。商业银行资本充足率与风险资产这种相互影响的关系为商业银行风险资产管理提供了理论依据。