Esa Jokivuolle

Portfolio Effects and Efficiency of Lending under Basel II

Although beneficial allocational effects have been a central motivation for the Basel II capital adequacy reform, the interaction of these effects with Basel IIs procyclical impact has been less discussed. In this paper, we investigate the effect of Basel II on the efficiency of bank lending. We consider competitive credit markets where entrepreneurs may apply for loans for investments of different risk profiles. In this setting, excessive risk taking typically arises because low risk borrowers cross-subsidize high risk borrowers through the price system that is based on average success rates. We find that while flat-rate capital requirements (such as Basel I) amplify overinvestment in risky projects, risk-based capital requirements alleviate the cross-subsidization effect, improving allocational efficiency. This also suggests that Basel II does not necessarily lead to exacerbation of macroeconomic cycles because the reduction in the proportion of high-risk investments softens the cyclicality of bank lending over the business cycle. Key words: Basel II, bank regulation, capital requirements, credit risk, procyclicality JEL classification numbers: D41, D82, G14, G21, G28

Bonus Caps, Deferrals and Bankers' Risk-Taking

Regulators restrict bankers’ risk-taking by bonus caps or deferrals. We derive a structural model to analyze these compensation regulations and show that for a risk-neutral banker subject to positive switching costs of reducing bank risk, a bonus deferral is impotent while a sufficiently tight bonus cap reduces risk-taking. The model suggests that a bonus cap that equals fixed salary (as in the EU) reduces risk on average by 13% under conservatively calibrated positive switching costs. Further, the bonus cap would have considerably reduced risk-taking incentives in most US banks that did poorly during the global financial crisis. We also show that the bonus deferral is effective if the banker is risk-averse and the switching costs are not too high.

Macro-Model-Based Stress Testing of Basel II Capital Requirements

Basel II framework requires banks to conduct stress tests on their potential future minimum capital requirements and consider ‘at least the effect of mild recession scenarios’. We propose a stress testing framework for minimum capital requirements in which banks’ corporate credit risks are modeled with macroeconomic variables. We can thus define scenarios such as a mild recession and consider the resulting credit risk developments and consequent changes in minimum capital requirements. We also emphasize the importance of stress testing future minimum capital requirements jointly with credit losses. Our illustrative results based on Finnish data underline the importance of such joint modeling. We also find that stress tests based on scenarios envisaged by regulators are not likely to imply binding capital constraints on banks.

The New Basel Accord: Some Potential Implications of the New Standards for Credit Risk

This paper discusses some potential implications - both intended and unintended - of The New Basel Accord, which is to be finalized by the end of 2001.Our focus is on the reforms of the rules for determining minimum capital requirements for credit risk.The discussion is divided into effects at the level of an individual bank, effects on the structure of the financial markets, and macroeconomic implications.We present a survey of potential effects rather than a profound analysis of any of them.Therefore conclusions are inevitably preliminary, and in many cases they are likely to be controversial.Although the new capital accord as a whole is a major improvement on many properties of the current framework, our aim is to find potential problems that might need to be considered in the implementation and application of the new rules.Overall, the new accord will be largely an experiment, of which many of the consequences remain to be seen.Key words: The New Basel Accord, capital adequacy requirements, credit crisk, banking stability

Informed Trading, Short Sales Constraints, and Futures' Pricing

The purpose of this paper is to provide an explanation for relative pricing of futures contracts with respect to underlying stocks using a model incorporating short sales constraints and informational lags between the two markets. In this model stocks and futures are perfect substitutes, except for the fact that short sales are only allowed in futures markets. The futures price is more informative than the stock price, because the existence of short sales constraints in the stock market prohibits trading in some states of the world. If an informed trader with no initial endowment in stocks receives negative information about the common future value of stocks and futures, he is only able to sell futures. Uninformed traders also face a similar short sales constraint in the stock market. As a result of the short sales constraint, the stock price is less informative than the futures price even if the informed trader has received positive information. Stocks can be under- and overpriced in comparison with futures, provided that market makers in stocks and futures only observe the order flow in the other market with a lag. Our theory implies that: 1) the basis is positively associated with the contemporaneous futures returns; 2) the basis is negatively associated with the contemporaneous stock return; 3) futures returns lead stock returns; 4) stock returns also lead futures returns, but to a lesser extent; and 5) the trading volume in the stock market is positively associated with the contemporaneous stock return. The model is tested using daily data from the Finnish index futures markets. Finland provides a good environment for testing our theory, since short sales were not allowed during the period for which we have data (27 May 1988 - 31 May 1994). We find strong empirical support for the implications of our theory.

Leverage Ratio Requirement and Credit Allocation Under Basel III

We show in a theoretical model that the introduction of the leverage ratio requirement, when it interacts with the risk-based IRB capital requirements, might lead to less lending to low-risk customers and to increased lending to high-risk customers. If such allocational effects are counter-productive to financial stability, then they may pose a trade-off against the alleged positive financial stability effects of the leverage ratio requirement.

Credit allocation, capital requirements and procyclicality

Although beneficial allocational effects have been a central motivator for the Basel II capital adequacy reform, the interaction of these effects with Basel II’s procyclical impact has been less discussed. In this paper, we investigate the effect of capital requirements on the allocation of credit and its interaction with procyclicality, and compare Basel I and Basel II type capital requirements. We consider competitive credit markets where entrepreneurs of varying ability can apply for loans for one-period investment projects of two different risk types. The risk of a project further depends on the state of the economy, modelled as a two-state Markov process. In this type of setting, excessive risk taking typically arises because higher-type borrowers cross-subsidize lower-type borrowers via a pricing regime based on average success rates. We find that risk-based capital requirements (such as Basel II) alleviate the cross-subsidization effect and can be chosen so as to implement first-best allocation. This implies that the ensuing reduction in the proportion of high-risk investments may mitigate the procyclical effect of Basel II on economic activity. Moreover, we find that optimal risk-based capital requirements should be set lower in recessions than in normal times. Our simulations show that when measured by either cumulative output or output variation, Basel II type capital requirements may actual be slightly less procyclical than flat capital requirements. The biggest reduction in procyclicality is however achieved with optimal risk-based capital requirements which are considerably higher than Basel II requirements and which are adjusted downwards in recession periods.

Rating targeting and the confidence levels implicit in bank capital

The solvency standards implicit in bank capital levels, as reported eg in Jackson et al (2002), are much higher than those required for top ratings, if standard single period economic capital models are taken seriously.We explain this excess capital puzzle by forward looking rating targeting behaviour by banks, which aims at maintaining rating above a minimum target in future periods.We calibrate to data on actual bank capital the confidence level used by the median US AA rated bank to maintain at least a single A rating.The calibrated confidence level is in line with the historical probability of an AA rated bank to be downgraded below A. Key words: bank capital, credit rating, value-at-risk, economic capital, capital structure JEL classification numbers: G21, G32

Transmission of macro shocks to loan losses in a deep crisis: the case of Finland

Building on the work of Sorge and Virolainen (2006), we revisit the data on aggregate Finnish bank loan losses from the corporate sector, which covers the ‘Big Five’ crisis in Finland in the early 1990s. Several extensions to the empirical model are considered. These extensions are then used in the simulations of the aggregate loan loss distribution. The simulation results provide some guidance as to what might be the most important dimensions in which to improve the basic model. We found that making the average LGD depend on the business cycle seems to be the most important improvement. We also compare the empirical fit of the annual expected losses over a long period. In scenario-based analyses we find that a prolonged deep recession (as well as simultaneity of various macro shocks) has a convex effect on cumulative loan losses. This emphasizes the importance of an early policy response to a looming crisis. Finally, a comparison of the loan loss distribution on the eve of the 1990s crisis with the most recent distribution demonstrates the greatly elevated risk level prior to the 1990s crisis.

GDP at Risk in a DSGE Model: An Application to Banking Sector Stress Testing

We suggest a complementary tool for financial stability analysis based on stochastic simulation of a dynamic stochastic general equilibrium model (DSGE) of the macro economy. The paper relates to financial stability research in which financial aggregates crucial to financial stability are modelled as functions of macroeconomic variables. In these models, stress tests for eg banking sector loan losses can be generated by considering adverse scenarios of macro variables. A DSGE model provides a systematic way of generating coherent macro scenarios which can be given a rigorous economic interpretation. The approach is illustrated using a DSGE model of the Finnish economy and a simple model of Finnish banking sector loan losses.