Liliana Schumacher

The Determinants of Bank Interest Rate Margins: An International Study

Abstract This paper studies the determinants of bank net interest margins (NIMs) in six selected European countries and the US during the period 1988–1995 for a sample of 614 banks. We apply the Ho and Saunders model (Ho, T., Saunders, A., 1981. The determinants of bank interest margins: theory and empirical evidence. Journal of Financial and Quantitative Analyses 16, 581–600) to a multicountry setting and decompose bank margins into a regulatory component, a market structure component and a risk premium component. The regulatory components in the form of interest-rate restrictions on deposits, reserve requirements and capital-to-asset ratios have a significant impact on banks NIMs. The empirical results suggest an important policy trade-off between assuring bank solvency—high capital-to-asset ratios—and lowering the cost of financial services to consumers—low NIMs. The more segmented or restricted the banking system—both geographically and by activity—the larger appears to be the monopoly power of existing banks, and the higher their spreads. Macro interest-rate volatility was found to have a significant impact on bank NIMs; this suggests that macro policies consistent with reduced interest-rate volatility could have a positive effect in reducing bank margins.

The Determinants of Commercial Bank Profitability in Sub-Saharan Africa

Bank profits are high in Sub-Saharan Africa (SSA) compared to other regions. This paper uses a sample of 389 banks in 41 SSA countries to study the determinants of bank profitability. We find that apart from credit risk, higher returns on assets are associated with larger bank size, activity diversification, and private ownership. Bank returns are affected by macroeconomic variables, suggesting that macroeconomic policies that promote low inflation and stable output growth does boost credit expansion. The results also indicate moderate persistence in profitability. Causation in the Granger sense from returns on assets to capital occurs with a considerable lag, implying that high returns are not immediately retained in the form of equity increases. Thus, the paper gives some support to a policy of imposing higher capital requirements in the region in order to strengthen financial stability.

Bank Runs and Currency Run in a System Without a Safety Net: Argentina and the 'Tequila' Shock

This paper tests the random-withdrawals vs. informed-based theories of bank runs in the context of the bank panic that took place in Argentina as a consequence of the Mexican devaluation of December 20, 1994. This evidence is unique in several ways: it is the case of a contemporary banking system with virtually no explicit safety net (a currency board with no deposit insurance scheme) and a case in which the bank runs were triggered by a currency run. The findings of the paper provide support to the informed-based theories and show that depositors are concerned with the impact of a currency run on bank solvency.

Financial Deepening in Sub-Saharan Africa: Empirical Evidence on the Role of Creditor Rights Protection and Information Sharing

This paper investigates the role of creditor rights and information sharing in explaining why some financial markets in sub-Saharan Africa have remained shallow. The paper finds that while financial liberalization and macroeconomic stability promote financial deepening, they are not enough. For countries with similar financial liberalization efforts, those with stronger legal institutions and information sharing have deeper financial development. This result is consistent with a growing body of research for other regions of the world. The main policy implications are that (1) creditor rights legislation should be reinforced, the law reformed, and efficient property registries established; and (2) governments should sponsor credit bureaus where private bureaus might not be commercially viable.

Measuring Integrated Market and Credit Risks in Bank Portfolios : An Application to a Set of Hypothetical Banks Operation in South Africa

The banking crises of the 1990s emphasize the need to model the connections between volatility and the potential losses faced by financial institutions due to correlated market and credit risks. We present a simulation model that explicitly links changes in the financial environment and the distribution of future bank capital ratios. This forward-looking quantitative risk assessment methodology allows banks and regulators to identify risks before they materialize and make appropriate adjustments to banks` portfolios. This model was applied to the study of the risk profile of the largest South African banks in the context of the Financial System Stability Assessment (FSSA) (1999).

Assessing Financial System Vulnerabilities

Recent financial crises have highlighted the potentially significant macroeconomic costs of financial system instability, and the potential for the instability in the financial system of one country to have broader implications for the stability of financial systems and macroeconomic performance in other countries. This paper reviews the different analytical approaches to assessing vulnerabilities in the financial systems and the benefits and limitations of the different approaches, and suggests enhancements that could help strengthen financial system stability assessments.

Modeling Correlated Systemic Liquidity and Solvency Risks in a Financial Environment with Incomplete Information

This paper proposes and demonstrates a methodology for modeling correlated systemic solvency and liquidity risks for a banking system. Using a forward looking simulation of many risk factors applied to detailed balance sheets for a 10 bank stylized United States banking system, we analyze correlated market and credit risk and estimate the probability that multiple banks will fail or experience liquidity runs simultaneously. Significant systemic risk factors are shown to include financial and economic environment regime shifts to stressful conditions, poor initial loan credit quality, loan portfolio sector and regional concentrations, bank creditors’ sensitivity to and uncertainties regarding solvency risk, and inadequate capital. Systemic banking system solvency risk is driven by the correlated defaults of many borrowers, other market risks, and inter-bank defaults. Liquidity runs are modeled as a response to elevated solvency risk and uncertainties and are shown to increase correlated bank failures. Potential bank funding outflows and contractions in lending with significant real economic impacts are estimated. Increases in equity capital levels needed to reduce bank solvency and liquidity risk levels to a target confidence level are also estimated to range from 3 percent to 20 percent of assets. For a future environment that replicates the 1987-2006 volatilities and correlations, we find only a small risk of U.S. bank failures focused on thinly capitalized and regionally concentrated smaller banks. For the 2007-2010 financial environment calibration we find substantially elevated solvency and liquidity risks for all banks and the banking system.

Central Banks Use of Derivatives and Other Contingent Liabilities: Analytical Issues and Policy Implications

Whereas some central bank derivatives and other contingent liabilities arise from anomalous circumstances, there are a number of positive reasons that explain their popularity. After analyzing the rationale for these operations, we stress that most of these operations, being off-balance sheet, increase the risk and reduce the transparency of central bank accounts. This in turn makes more difficult the assessment of the financial position of the monetary authority and, by implication, of the macroeconomic conditions of the country. To deal with this issue, we suggest a comprehensive portfolio approach that values, in an economic sense, all assets and liabilities of the central bank.

Bank Solvency and Funding Cost

Understanding the interaction between bank solvency and funding cost is a crucial pre-requisite for stress-testing. In this paper we study the sensitivity of bank funding cost to solvency measures while controlling for various other measures of bank fundamentals. The analysis includes two measures of bank funding cost: (a) average funding cost and (b) interbank funding cost as a proxy of wholesale funding cost. The main findings are: (1) Solvency is negatively and significantly related to measures of funding cost, but the effect is small in magnitude. (2) On average, the relationship is stronger for interbank funding cost than for average funding cost. (3) During periods of stress interbank funding cost is more sensitive to solvency than in normal times. Finally, (4) the relationship between funding cost and solvency appears to be non-linear, with higher sensitivity of funding cost at lower levels of solvency.

Market Volatility as a Financial Soundness Indicator: An Application to Israel

Financial decisions of economic agents are based on volatility considerations. However, no aggregate indicators have been used by policymakers and regulators to assess the market risk environment. This paper applies a market volatility indicator to analyze the Israelis transition toward inflation targeting. Unlike conventional measures of volatility, it shows a substantial decline once volatility is measured against the minimum variance for the same returns on assets. Using a conventional Multivariate GARCH model, we find that interest rates sensitivity to changes in the risk environment may be important for a correct identification of volatility patterns of individual assets.