Capital shocks, bank asset allocation, and the revised Basel Accord

In contrast to the 1988 Basel Accord (Basel I), the revised risk-based capital standards (Basel II) propose regulatory capital requirements based on credit ratings. This paper develops a theoretical model to analyze how banks will adjust their low and high credit risk commercial loans under the proposed newer standard. Capital-constrained banks respond to an adverse capital shock by reducing high credit risk loans, while under certain circumstances, low credit risk loans may actually increase. When compared to Basel I, it is shown that high-risk loans are reduced more under Basel II, but whether a bank reduces total lending more under Basel I or under the revised standards depends on a complex interaction of factors.     

Potential Competitive Effects of Basel II on Banks in SME Credit Markets in the United States

We examine the likely competitive effects of implementation of Basel II capital requirements on banks in the market for credit to SMEs in the U.S. Similar competitive effects from Basel II may occur for other credits and financial instruments in the U.S. and other nations. We address whether reduced risk weights for SME credits extended by large banking organizations that adopt the Advanced Internal Ratings-Based (A-IRB) approach of Basel II might significantly adversely affect the competitive positions of other organizations. The analyses suggest only relatively minor competitive effects on most community banks because the large A-IRB adopters tend to make very different types of SME loans to different types of borrowers than community banks. However, there may be significant adverse effects on the competitive positions of large non-A-IRB banking organizations because the data do not suggest any strong segmentation in SME credit markets among large organizations. JEL classification: G21, G28, G38, L51     

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.     

A Critique of Revised Basel II

This paper critiques the revised Basel II capital requirements for banks. To provide a framework for analysis, the XYZ theory of regulatory capital is formulated. Independent of the XYZ theory, we argue that the revised Basel II capital rule for credit risk is not a good approximation to the ideal rule. Based on this, and using the XYZ theory, we argue that: (1) the revised Basel II rules should not replace the existing approaches for determining minimal capital standards, but should be used in conjunction with them, and (2) that calibrating the capital rules to maintain aggregate market capital is a prudent procedure.     

Competitive effects of Basel II on US bank credit card lending

We analyze the potential competitive effects of the proposed Basel II capital regulations on US bank credit card lending. We find that bank issuers operating under Basel II will face higher regulatory capital minimums than Basel I banks, with differences due to the way the two regulations treat reserves and gain-on-sale of securitized assets. During periods of normal economic conditions, this is not likely to have a competitive effect; however, during periods of substantial stress in credit card portfolios, Basel II banks could face a significant competitive disadvantage relative to Basel I banks and nonbank issuers.     

资本计量方法改革、商业银行风险偏好与信贷配置

为提高银行业风险管理水平与信贷配置效率,监管部门于2014年开展了资本管理高级方法的试点工作。本文基于上市银行2010至2016年的微观数据,与银监会公布的行业信贷风险进行匹配,采用双重差分和三重差分法,实证分析前述改革如何影响试点银行的风险偏好和信贷调配。研究发现,在资本管理高级方法实施后:(1)试点银行显著降低了风险加权资产的规模;(2)试点银行风险偏好的变化存在非线性的特征,在调减高风险行业贷款的同时,并未显著增加最安全行业的贷款,而是增加了风险略高行业的贷款,体现出试点银行对风险与收益的权衡;(3)进一步将行业划分为“虚”与“实”,研究发现试点银行减少了房地产业(“虚”)、制造业(“实”)和建筑业(“实”)贷款,显著增加了金融业(“虚”)贷款。本文研究不仅丰富了资本监管方面的文献,也对金融支持供给侧结构性改革具有启示意义。     

Capital requirements under the credit risk-based framework

This work aims to study the hypothesis of lower capitalization of banks under the risk-based rules introduced in Basel II. In this sense, an assessment of the impact of these rules on the capital requirements for non-financial firms’ credit risk is performed. A comparison with Basel I is presented and intervals of variation for the risk drivers such that capital requirements exceed the ones under Basel I are established. Data for a European country supports the hypothesis of a smaller capitalization of banks under the risk-based framework, as far as credit risk in concerned.     

Basel II vs. Prompt Corrective Action: Which Is Best for Public Policy?

This paper evaluates Basel II as a tool for achieving public policy objectives relative to structured early intervention and resolution (SEIR) and prompt corrective action (PCA) in the U.S. It concludes that Basel II compares poorly in terms of maintaining a safe and sound banking system. Rather, Basel II resembles a "best practices" guide for banks in managing their credit risk. However, it may do damage through encouraging some large banks in the U.S. to successfully pressure their regulators to lower the capital trigger ratio for "adequately‐capitalized" status in order to benefit from any lower regulatory capital requirement that Basel II may give them.     

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.     

Transitional credit modelling and its relationship to market value at risk: an Australian sectoral perspective

Internal credit risk modelling is important for banks for the calculation of capital adequacy in terms of the Basel Accords, and for the management of sectoral exposure. We examine Credit Value at Risk (VaR), Conditional Credit Value at Risk (Credit CVaR) and the relationship between market and credit risk. Significant association is found between different Credit CVaR methods, and between market and credit risk. Simpler Credit CVaR methods are found to be viable alternatives to more complex methodology. The relationship between market and credit risk is used to develop a new model that allows banks to incorporate industry risk into transition modelling, without macroeconomic analysis.     

Investigating the dependence structure between credit default swap spreads and the U.S. financial market

Under Basel II framework, credit risk assessment is of high significance in the light of correlation risk. Correlation risk is often envisioned along with business conditions and financial market’s impact. We employ copula methodology to identify the dependence structures that may exist between market risk fundamentals and credit risk fundamentals. Considering credit derivative spreads as credit risk fundamentals and market data as market risk determinants, we describe and quantify the asymmetric link prevailing between credit risk and market risk. Credit risk is negatively linked with market price risk whereas it becomes positively linked with market volatility risk. Such patterns give rise to interesting asymmetric dependence structures between both risk sources. We are then able to balance reliably market price risk with market volatility feedback, the market trend supporting a common correlation between securities. In the light of the previous trade-off, we propose also a simple credit risk management rule.     

Credit risk transfer activities and systemic risk: How banks became less risky individually but posed greater risks to the financial system at the same time

A main cause of the crisis of 2007-2009 is the various ways through which banks have transferred credit risk in the financial system. We study the systematic risk of banks before the crisis, using two samples of banks respectively trading Credit Default Swaps (CDS) and issuing Collateralized Loan Obligations (CLOs). After their first usage of either risk transfer method, the share price beta of these banks increases significantly. This suggests the market anticipated the risks arising from these methods, long before the crisis. We additionally separate this beta effect into a volatility and a market correlation component. Quite strikingly, this decomposition shows that the increase in the beta is solely due to an increase in banks’ correlations. Thus, while banks may have shed their individual credit risk, they actually posed greater systemic risk. This creates a challenge for financial regulation, which has typically focused on individual institutions.     

Credit Risk Versus Capital Requirements under Basel II: Are SME Loans and Retail Credit Really Different?

Under Basel II, retail and SME credit (R&SME) receive special treatment because of a supposedly smaller exposure to systemic risk. Most research on this issue has been based on parameterized credit risk models. We present new evidence by applying Carey's (Carey, Mark. “Credit Risk in Private Debt Portfolios.” Journal of Finance 53, no. 4 (1998), 1363–1387.) nonparametric Monte-Carlo resampling method to two banks' complete loan portfolios. By exploiting that a sub-sample of all borrowers has been assigned an internal rating by both banks, we can compare the credit loss distributions for the three credit types, and compute both economic and regulatory capital under Basel II. We also test if our conclusions are sensitive to the definitions of R&SME credit. Our findings show that R&SME portfolios are usually riskier than corporate credit. Special treatment under Basel II is thus not justified. JEL classification: C14, C15, G21, G28, G33.     

Financial stability and Basel II

The Basel II Advanced Internal Ratings (AIRB) approach is compared to capital requirements set using an equilibrium structural credit risk model. Analysis shows the AIRB approach undercapitalizes credit risk relative to regulatory targets and allows wide variation in capital requirements for a given exposure owing to ambiguity in the definitions of loss given default and exposure at default. In contrast, the Foundation Internal Ratings Based (FIRB) approach may over-capitalize credit risk relative to supervisory objectives. It is unclear how Basel II will buttress financial sector stability as it specifies the weakest regulatory capital standard for large complex AIRB banks.      

Regulatory and “economic” solvency standards for internationally active banks

One of the most important policy issues for financial authorities is to decide at what level average capital charges should be set. The decision may alternatively be expressed as the choice of an appropriate survival probability for representative banks over a horizon such as a year, often termed a “solvency standard”. This article sheds light on the solvency standards implied by current and possible future G10 bank regulation and on the “economic solvency standard” that banks choose themselves by their own capital setting decisions. In particular, we employ a credit risk model to show that the survival probability implied by the 1988 Basel Accord is between 99.0% and 99.9%. We then demonstrate that if a new Basel Accord were calibrated to such a standard, it would not represent a binding constraint on banks' current operations since most banks employ a solvency standard higher than 99.9%. To show this, we employ a statistical analysis of bank ratings adjusted for the impact of official or other support as well as credit risk model calculations. Lastly, we advance a possible explanation for the conservative capital choices made by banks by showing that swap volumes are highly correlated with credit quality for given bank size. This suggests that banks' access to important credit markets like the swaps markets may provide a significant discipline in the choice of solvency standard.     

An Assessment of Basel II Procyclicality in Mortgage Portfolios

In this paper we develop a probability of default (PD) model for mortgage loans, taking advantage of the Spanish Credit Register, a comprehensive database on loan characteristics and credit quality. From that model, we calculate different types of PDs: point in time, PIT, through the cycle, TTC, average across the cycle and acyclical. Then, we compare capital requirements coming from the different Basel II approaches. We show that minimum regulatory capital under Basel II can be very sensitive to the risk measurement methodology employed. Thus, the procyclicality of regulatory capital requirements under Basel II is an open question, depending on the way internal rating systems are implemented and their output is utilised. We focus on the mortgage portfolio since it is one of the most under researched areas regarding the impact of Basel II and because it is one of the most important of banks’ portfolios.     

Can regulators allow banks to set their own capital ratios?

Basel regulators have received widespread criticism for failing to prevent two credit crises that hit the U.S. over the last two decades. Nonetheless, banks were considerably overcapitalized prior to the onset of the 2007–2009 subprime crisis compared to those which had undergone the 1990–1991 recession. Therefore, if capital requirements were achieved prior to the subprime crisis, how could the Basel framework be blamed again for having accelerated if not caused another credit crunch? We find that the answer to this question lies in the relationship between the capital ratio and the leverage ratio which is governed by risk-weights categories determined by the Basel regulation. We show that changes to risk-weight categories which affect the correlation pattern between both ratios are not reflected in the subprime crisis. This minimizes the implication of the Basel II regulation in the crunch that succeeded its announcement, in contrast to Basel I. We demonstrate that these dynamics are governed by a formula linking the two ratios together which derives from the sensitivity of the risk-based capital ratio to a change in its risk-weight(s). One implication of our work regarding the Basel III regulation consists in validating the newly established capital increments in a mathematical rather than heuristical approach.     

Credit risk in the leasing industry

This paper is devoted to the credit risk modeling issues of retail lease portfolios. Using a re-sampling method, I estimate the probability density function of losses and VaR measures in a portfolio of 46,732 leases issued between 1990 and 2000 by a major European financial institution. My results show that physical collaterals play a major role in reducing the credit risk associated with lease portfolios. However, because of insufficient recognition of such collaterals under the new regulatory capital framework (Basel II), significant differences are observed between the estimated capital requirements and those calculated in accordance with the various Basel II approaches.     

Modelling Deposit Insurance Scheme Losses in a Basel 2 Framework

This paper extends the existing literature on deposit insurance by proposing a new approach for the estimation of the loss distribution of a Deposit Insurance Scheme (DIS) that is based on the Basel 2 regulatory framework. In particular, we generate the distribution of banks’ losses following the Basel 2 theoretical approach and focus on the part of this distribution that is not covered by capital (tail risk). We also refine our approach by considering two major sources of systemic risks: the correlation between banks’ assets and interbank lending contagion. The application of our model to 2007 data for a sample of Italian banks shows that the target size of the Italian deposit insurance system covers up to 98.96% of its potential losses. Furthermore, it emerges that the introduction of bank contagion via the interbank lending market could lead to the collapse of the entire Italian banking system. Our analysis points out that the existing Italian deposit insurance system can be assessed as adequate only in normal times and not in bad market conditions with substantial contagion between banks. Overall, we argue that policy makers should explicitly consider the following when estimating DIS loss distributions: first, the regulatory framework within which banks operate such as (Basel 2) capital requirements; and, second, potential sources of systemic risk such as the correlation between banks’ assets and the risk of interbank contagion.     

Asset correlations and bank capital adequacy

This paper addresses the estimation of confidence sets for asset correlations used in credit risk portfolio models. Research on the estimation of asset correlations using endogenous probabilities of default estimations has focused on the impact of concentration risk factors, such as firm size and industry. The empirical evidence from Italian small- and medium-size companies show that the assumptions underlying the Basel Committee regulatory capital risk weight function are not substantiated. The regulatory impact is that the capital adequacy is significantly compromised, driving an adverse selection, which favors the worst companies, and transferring the procyclical effects from firms to banks.