Stress Testing

After completing this reading, you should be able to:

• Describe the rationale for the use of stress testing as a risk management tool.
• Describe the relationship between stress testing and other risk measures, particularly in enterprise-wide stress testing.
• Describe stressed VaR and stressed ES, including their advantages and disadvantages, and compare the process of determining stressed VaR and ES to that of traditional VaR and ES.
• Explain key considerations and challenges related to developing stress testing scenarios and building stress testing models.
• Describe reverse stress testing and describe an example of regulatory stress testing.
• Describe the responsibilities of the board of directors, senior management, and the internal audit function in stress testing governance.
• Describe the role of policies and procedures, validation, and independent review in stress testing governance.
• Describe the Basel stress testing principles for banks regarding the implementation of stress testing.

Stress testing is a risk management tool that involves analyzing the impacts of the extreme scenarios that are unlikely but feasible. The main question for financial institutions is whether they have adequate capital and liquid assets to survive stressful times. Stress testing is done for regulatory purposes or for internal risk management by financial institutions. Stress testing can be combined with measurement of the risk such as the Value-at-Risk (VaR) and the Expected Shortfall (ES) to give a detailed picture of the risks facing a financial institution.

This chapter deals with the internally generated stress testing scenarios, regulatory requirements of stress testing, governance issues of stress testing, and the Basel stress testing principles.

Rationale for the Use of Stress Testing as a Risk Management Tool

• Stress testing serves to warn a firm’s management of potential adverse events arising from the firm’s risk exposure and goes further to give estimates of the amount of capital needed to absorb losses that may result from such events.
• Stress tests help to avoid any form of complacency that may creep in after an extended period of stability and profitability. It serves to remind management that losses could still occur, and adequate plans have to be put in place in readiness for every eventuality. This way, a firm is able to avoid issues like underpricing of products, something that could prove financially fatal.
• Stress testing is a key risk management tool during periods of expansion when a firm introduces new products into the market. There may be very limited loss data or none at all, for such products, and hypothetical stress testing helps to come up with reliable loss estimates.
• Under pillar 1 of Basel II, stress testing is a requirement of all banks using the Internal Models Approach (IMA) to model market risk and the internal ratings-based approach to model credit risk. These banks have to employ stress testing to determine the level of capital they are required to have.
• Stress testing supplements other risk management tools, helping banks to mitigate risks through measures such as hedging and insurance. By itself, stress testing cannot address all risk management weaknesses, nor can it provide a one-stop solution.

Relationship Between Stress Testing and Other Risk Measures in Enterprise-Wide Context

In essence, stress testing extends the range of analysis offered by traditional risk measures like VaR and ES, by examining the effects of systemic crises and severe market conditions that may not be captured in everyday risk management metrics. It plays a critical role in strategic risk management, particularly at an enterprise-wide level, by providing insights into the effect of extreme but conceivable scenarios on an institution’s overall health, guiding both internal risk management and satisfying regulatory requirements.

Enterprise-wide stress testing seeks to provide a comprehensive view of risks across an entire financial institution. It involves integrating risks from all business units and assessing the effects of specific scenarios on the financial condition of the firm as a whole.

To simulate enterprise-wide scenarios, stress testing often employs macroeconomic variables which are critical inputs for reflecting broad economic and financial conditions. These may include GDP growth rates, unemployment rates, interest rates, and others which affect the institution’s portfolio in diverse and interconnected ways.

Stress testing measures how sensitive a firm’s operations and financial stability are to the changes in macroeconomic factors. It examines the potential effects on income, liquidity, and capital adequacy, creating a narrative of cause-and-effect that stretches across the institution’s entire portfolio.

Stress testing is instrumental to strategic planning and risk management as it helps identify vulnerabilities across the firm’s business lines and informs decisions regarding capital allocation, investment strategies, and risk appetite settings.

It also plays a vital role in regulatory compliance, serving as a tool for regulators to ascertain that financial institutions maintain adequate capital reserves to withstand severe market disruptions. This facilitates a more resilient financial system.

Stressed VaR and Stressed ES: Concepts and Comparisons

Recall that the VaR and ES are estimated from a loss distribution. VaR enables a financial institution to conclude with X% likelihood that the losses will not exceed the VaR level during time T. On the other hand, ES enables the financial institutions to conclude whether the losses exceed the VaR level during a given time T and hence the expected loss will be the ES amount.

VaR and ES are backward-looking. That is, they assume that the future and the past are the same. This is actually one disadvantage of VaR and ES. On the other hand, stress testing is forward-looking. It asks the question, “what if?”.

While stress testing largely does not involve probabilities, VaR, and ES models are founded on probability theory. For example, a 99.9% VaR can be viewed as a 1-in-1,000 event.

The backward-looking ES and VaR consider a wide range of scenarios that are potentially good or bad to the organization. However, stress testing considers a relatively small number of scenarios that are all bad for the organization.

Specifically, for the market risk, VaR/ES analysis often takes a short period of time, such as a day, while stress testing takes relatively long periods, such as a decade.

The primary objective of stress testing is to capture the enterprise view of the risks impacting a financial institution. The scenarios used in the stress testing are often defined based on the macroeconomic variables such as the unemployment rates and GDP growth rates. The effect of these variables should be considered in all parts of an institution while considering interactions between diverse areas of an institution.

Stressed VaR and Stressed ES

Conventional VaR and ES are calculated from data spanning from one to five years, where a daily variation of the risk factors during this period is used to compute the potential future movements.

However, in the case of the stressed VaR and stressed ES, the data is obtained from specifically stressed periods (12-month stressed period on current portfolios according to Basel rules). In other words, stressed VaR and stressed ES generates conditional distributions and conditional risk measures. As such, they are conditioned to a recurrence of a given stressed period and thus can be taken as a historical stress testing.

Though stressed VaR and stressed ES might be objectively similar, they are different. Typically the time horizon for the stressed VaR/ES is short (one to ten days), while for the stress testing, it considers relatively longer periods.

For instance, assume that a stressed period is the year 2007. The stressed VaR would conclude that if there was a repeat of 2007, then there is an X% likelihood that losses over a period of T days will not surpass the stressed VaR level. On the other hand, stressed ES would conclude that if the losses over T days do not exceed the stressed VaR level, then the expected loss is the stressed ES.

However, stress testing would ask the questions “if the following year (2008) is the same as in 2007, will the financial institution survive?” Alternatively, what if the conditions of the next year are twice as adverse as that of 2007, will the financial institution survive? Therefore, stress testing does not consider the occurrence of the worst days of 2008 but rather the impact of the whole year.

There is also a difference between conventional VaR and the stressed VaR. Conventional VaR can be back-tested while stressed VaR cannot. That is, if we can compute one-day VaR with 95% confidence, we can go back and determine how effective it would have worked in the past. We are not able to back-test the stressed VaR output and its results because it only considers the adverse conditions which are generally infrequent.

Advantages of Stressed VaR and Stressed ES

• Enhanced Risk Sensitivity: These stressed measures are designed to be more sensitive to the type of extreme market conditions that could lead to significant financial distress, providing a better assessment of potential risks under severe economic stress.

• Regulatory Compliance: Stressed VaR and stressed ES are aligned with regulatory standards, such as those imposed by Basel III, which mandates banks to incorporate stressed conditions into their risk metrics to ensure they hold sufficient capital to weather extreme financial downturns.

Disadvantages of Stressed VaR and Stressed ES

• Lack of Backtesting Capability: Unlike traditional VaR, stressed VaR cannot be easily backtested because the data pertains to rare, extreme market conditions that do not occur frequently. This limitation also applies to stressed ES, as it derives from stressed VaR calculations.

• Potential Overestimation of Risk: Since stressed VaR and stressed ES are based on extreme conditions, there is a possibility that they may overestimate required capital reserves during more typical market conditions, leading to excess capital that could otherwise be deployed or returned to shareholders.

Key Considerations in Developing Stress Testing Scenarios

Selecting Relevant Scenarios

• Historical Scenarios: Involves using past market events, like the 2007-2008 financial crisis, to simulate the behavior of risk factors under similar stress conditions in the future. The relevance of these scenarios lies in their rootedness in actual events, providing tangible examples for potential stress conditions.

• Hypothetical Scenarios: These are constructed based on plausible but not yet realized events, such as geopolitical conflicts or unexpected economic collapses. They require creativity and forecasting abilities to estimate responses to unprecedented situations.

• Regulatory Scenarios: Often prescribed by regulatory authorities to ensure consistency and comparability across institutions. These scenarios help regulators gauge the system-wide impacts of specific stress events.

• Ad Hoc Stress Tests: Financial institutions need to develop ad hoc scenarios that capture the current economic conditions, specific exposures facing the firm, and update analysis of potential future extreme events. The firms either generate new scenarios or modify the existing scenarios based on previous data. An example of an event that will prompt the firms to develop an ad hoc scenario is the change in the government policy on an important aspect that impacts the financial institutions or change in Basel regulation that requires an increment of the capital within short periods of time.

Selecting Appropriate Time Horizons

• Short-term vs. Long-term: The time horizon of a stress scenario must align with the nature of the risks being tested and the objectives of the scenario itself. Short-term horizons might be appropriate for market risk-related stresses, while long-term horizons might be necessary for more structural risks, like credit or business risks.

• Alignment with Business Cycles: Scenarios should consider the business and economic cycles to ensure that the timing and duration of stress conditions realistically reflect potential real-world developments.

Incorporating Key Variables and Assumptions

• Key Risk Drivers: Identifying and incorporating critical risk drivers, such as interest rates, default rates, or exchange rates, into scenarios is crucial. These variables should be relevant to the institution’s portfolio and operations.

• Assumptions Documentation: All assumptions made in the creation of scenarios must be clearly documented, as they have a significant impact on the stress test outcomes. Transparent documentation supports the credibility and utility of the stress test results.

Using the Stress Testing Results

While stress testing, it is vital to involve the senior management for it to be taken seriously and thus used for decision making. The stress-testing results are not only used to satisfy the “what if” question, but also the Board and management should analyze the results and decide whether a certain class of risk mitigation is necessary. Stress testing makes sure that the senior management and the Board do not base their decision-making on what is most likely to happen, but also consider other alternatives less likely to happen that could have a dramatic result on the firm.

Model Building

It is possible to see how the majority of the relevant risk factors behave in a stressed period while building a scenario, after which the impact of the scenario on the firm is analyzed in an almost direct manner. However, scenarios generated by stressing key variables and ad hoc scenarios capture the variations of a few key risk factors or economic variables. Therefore, in order to exhaust the scenarios, it is necessary to build a model to determine how the “left out” variables are expected to behave in a stressed market condition. The variables stated in the context of the stress testing are termed as core variables, while the remaining variables are termed as peripheral variables.

One method is performing analysis, such as regression analysis, to relate the peripheral variables to the core variables. Note that the variables are based on the stressed economic conditions. Using the data of the past stressed periods is most efficient in determining appropriate relationships.

For example, in case of the credit risk losses, data from the rating agencies, such as default rates, can be linked to an economic variable such as GDP growth rate. Afterward, general default rates expected in various stressed periods are determined. The results can be modified (scaled up or down) to determine the default rate for different loans or financial institutions. Note that the same analysis can be done to the recovery rates to determine loss rates.

The Knock-On Effects

Apart from the immediate impacts of a scenario, there are also knock-on effects that reflect how financial institutions respond to extreme scenarios. In its response, a financial institution can make decisions that can further worsen already extreme conditions.

For instance, during the 2005-2006 US housing price bubble, banks were concerned with the credit quality of other banks and were not ready to engage in interbank lending, which made funding costs for banks rise.

Challenges in Building Stress Testing Models

Data Availability and Quality

• Historical Data: Accumulating adequate historical data that is representative of the assets or risks under scrutiny is often a challenge, particularly for new products or markets.

• Data Granularity: Fine-grained data might be needed to get an accurate picture of risk, which can sometimes be difficult to source or manage due to volume and complexity.

Model Complexity and Accuracy

• Modeling Approaches: Whether using statistical models, sensitivity analysis, or causal models, each approach has its strengths and limitations in terms of complexity and the accuracy of the results.

• Model Risk: The models may include simplifications or rely on insufficient data, leading to model risk—the risk that incorrect or inappropriate models may lead to understated or overstated stress impacts.

Accounting for Correlations and Feedback Loops

• Correlation Changes Under Stress: Risk factors that are normally weakly correlated may become highly correlated during stress periods, complicating the modeling process.

• Feedback Loops: Changes in market conditions can lead to actions by market participants that further exacerbate the stress (e.g., a bank run), requiring sophisticated modeling to capture these dynamics.

Scenario Reconciliation and Integration

• Multi-Scenario Analysis: Incorporating various scenarios into a single coherent framework poses challenges in reconciling different assumptions, interactions among risk types, and resultant impacts.

Model Validation and Review

• Validation Difficulty: Due to the nature of stress testing being forward-looking and based on hypothetical scenarios, validating the models and their predictive power is inherently challenging.

• Ongoing Review: Models need to be continually reviewed and updated to ensure they remain relevant, especially as market conditions and the regulatory landscape evolve.

Regulatory and Governance Considerations

• Regulatory Compliance: Staying compliant with the ever-changing regulatory requirements demands flexibility and adaptability in stress test models.

• Internal Governance: Ensuring that the stress testing process is well-governed within the institution requires clear roles, responsibilities, and accountability mechanisms.

Reverse Stress Testing

Recall that stress testing involves generating scenarios and then analyzing their effects. Reverse stress testing, as the name suggests, takes the opposite direction by trying to identify combinations of circumstances that might lead financial institutions to fail.

By using historical scenarios, a financial institution identifies past extreme conditions. Then, the bank determines the level at which the scenario has to be worse than the historical observation to cause the financial institution to fail. For instance, a financial institution might conclude that twice the 2005-2006 US housing bubble will make the financial institution to fail. However, this kind of reverse stress testing is an approximation. Typically, a financial institution will use complicated models that take into consideration correlations between different variables to make the market conditions more stressed.

Finding an appropriate combination of risk factors that lead the financial institution to fail is a challenging feat. However, an effective method is to identify some of the critical factors such as GDP growth rate, unemployment rates, and interest rate variations, then build a model that relates all other appropriate variables to these key variables. After that, possible factor combinations that can lead to failure are searched iteratively.

Regulatory Stress Testing

US, UK, and EU regulators require banks and insurance companies to perform specified stress tests. In the United States, the Federal Reserve performs stress tests of all the banks whose consolidated assets are over USD 50 billion. This type of stress test is termed as Comprehensive Capital Analysis and Review (CCAR). Under CCAR, the banks are required to consider four scenarios:

1. Baseline Scenario
2. Adverse Scenario
3. Severely Scenario
4. An internal Scenario

The baseline scenario is based on the average projections from the surveys of the economic predictors but does not represent the projection of the Federal Reserve.

The adverse and the severely adverse scenarios describe hypothetical sets of events which are structured to test the strength of banking organizations and their resilience. Each of the above scenarios consists of the 28 variables (such as the unemployment rate, stock market prices, and interest rates) which captures domestic and international economic activity accompanied by the Board explanation on the overall economic conditions and variations in the scenarios from the past year.

Banks are required to submit a capital plan, justification of the models used, and the outcomes of their stress testing. If a bank fails to stress test due to insufficient capital, the bank is required to raise more capital while restricting the dividend payment until the capital has been raised.

Banks with consolidated assets between USD 10 million and USD 50 million are under the Dodd-Fank Act Stress Test (DFAST). The scenarios in the DFAST are similar to those in the CCAR. However, in the DFAST, banks are not required to produce a capital plan.

Therefore, through stress tests, regulators can consistently evaluate the banks to determine their ability to extreme economic conditions. However, they recommend that banks develop their scenarios.

Responsibilities of the Board of Directors, Senior Management and the Internal Audit Function in Stress Testing Activities

For effective operation of stress testing, the Board of directors and senior management should have distinct responsibilities. What’s more, there should be some shared responsibilities, although a few roles can be set aside exclusively for one of the two groups.

Responsibilities of the Board of Directors

1. The buck stops with the Board: The Board of directors is “ultimately” responsible for a firm’s stress tests. Even if board members do not immerse themselves in the technical details of stress tests, they should ensure that they stay sufficiently knowledgeable about stress-testing procedures and interpretation of results.
2. Continuous involvement: Board members should regularly receive summary information on stress tests, including results from every scenario. Members should then evaluate these results to ensure they take into account the firm’s risk appetite and overall strategy.
3. Continuous review: Board members should regularly review stress testing reports with a view to not just critic key assumptions but also supplement the information with their views that better reflect the overall goals of the firm.
4. Integrating stress testing results in decision making: The Board should make key decisions on investment, capital, and liquidity based on stress test results along with other information. While doing this, the Board should proceed with a certain level of caution in cognizance of the fact that stress tests are subject to assumptions and a host of limitations.
5. Formulating stress-testing guidelines: It’s the responsibility of the Board to come up with guidelines on stress testing, such as the risk tolerance level (risk appetite).

Responsibilities of Senior Management

1. Implementation oversight: Senior management has the mandate to ensure that stress testing guidelines authorized by the Board are implemented to the letter. This involves establishing policies and procedures that help to implement the Board’s guidelines.
2. Regularly reporting to the Board: Senior management should keep the Board up-to-date on all matters to do with stress testing, including test designs, emerging issues, and compliance with stress-testing policies.
3. Coordinating and Integrating stress testing across the firm: Members of senior management are responsible for propagating widespread knowledge on stress tests across the firm, making sure that all departments understand its importance.
4. Identifying grey areas: Senior management should seek to identify inconsistencies, contradictions, and possible gaps in stress tests to make improvements to the whole process.
5. Ensuring stress tests have a sufficient range: In consultations with the Board of directors, senior management has to ensure that stress testing activities are sufficiently severe to gauge the firm’s preparation for all possible scenarios, including low-frequency high-impact events.
6. Using stress tests to assess the effectiveness of risk mitigation strategies: Stress tests should help the management to assess just how effective risk mitigation strategies are. If such strategies are effective, significantly severe events will not cause significant financial strain. If the tests predict significant financial turmoil, it could be that the hedging strategies adopted are ineffective.
7. Updating stress tests to reflect emerging risks: As time goes, an institution will gradually gain exposure to new risks, either as a result of market-wide trends or its investment activities. It is the responsibility of senior management to develop new stress-testing techniques that reflect the institution’s new risk profile.

Role of the Internal Audit 

Internal audit should:

• Independently evaluate the performance, integrity, and reliability of stress-testing activities;
• Ensure that stress tests across the organization are conducted in a sound manner and remain relevant in terms of the scenarios tested;
• Assess the skills and expertise of the staff involved in stress-testing activities;
• Check that approved changes to stress-testing policies and procedures are implemented and appropriately documented;
• Evaluate the independent review and validation exercises;

To accomplish all the above, internal audit staff must be well-qualified. They should be well-grounded in stress-testing techniques and technical expertise to be able to differentiate between excellent and inappropriate practices.

The Role of Policies and Procedures, Validation, and Independent Review in Stress Testing Governance

Policies and Procedures

A financial institution should set out clearly stated and understandable policies and procedures governing stress testing, which must be adhered to. The policies and procedures ensure that the stress testing of parts of a financial institution converges to the same point.

The policies and procedures should be able to:

• Explain the purpose of stress testing;
• Describe the procedures of stress testing;
• State the frequency at which the stress testing can be done;
• Describe the roles and responsibilities of the parties involved in stress testing;
• Provide an explanation of the procedures to be followed while choosing the scenarios;
• Describe how the independent reviews of the stress testing will be done;
• Give clear documentation on stress testing to third parties (e.g., regulators, external auditors, and rating agencies);
• Explain how the results of the stress testing will be used and by whom;
• They were amended as the stress testing practices changes as the market conditions change;
• Accommodate tracking of the stress test results as they change through time; and
• Document the activities of models and the software acquired from the vendors or other third parties.

Validation and Independent Review Governance

The stress testing governance covers the independent review procedures, which are expected to be unbiased and provide assurance to the board that stress testing is carried out while following the firm’s policies and procedures. Financial institutions use diverse models that are subject to independent review to make sure that they serve the intended purpose.

Validation and independent review should involve the following:

• Ensuring that validation and independent review are conducted on an ongoing basis;
• Ensuring that subjective or qualitative aspects of a stress test are also validated and reviewed, even if they cannot be tested in quantitative terms;
• Acknowledging limitations in stress testing;
• Ensuring that stress-testing standards are upheld;
• Acknowledging data weaknesses or limitations, if any;
• Ensuring that there is sufficient independence in both validation and review of stress tests;
• Ensuring that third-party models used in stress-testing activities are validated and reviewed to determine if they are fit for the purpose at hand;
• Ensuring that stress tests results are implemented rigorously, and verifying that any departure from the recommended actions is backed up by solid reasons.

Basel Stress-Testing Principles

The Basel Committee emphasizes that stress testing is a crucial aspect by requiring that the market risk calculations are based on the internal VaR and the Expected Shortfall (ES) models, which should be accompanied by “ rigorous and comprehensive” stress testing. Moreover, banks that use the internal rating approach of the Basel II to calculate the credit risk capital should perform a stress test to evaluate the strength of their assumptions.

Influenced by the 2007-2008 financial crisis, the Basel Committee published the principles of stress-testing for the banks and corresponding supervisors. The overarching emphasis of the Basel committee was the importance of stress testing in determining the amount of capital that will cushion banks against losses due to large shocks.

Therefore, the Basel committee recognized the importance of stress testing in:

• Giving a forward-looking perspective on the evaluation of risk;
• Overcoming the demerits of modes and historical data;
• Facilitating the development of risk mitigation, or any other plans to reduce risks in different stressed conditions;
• Assisting internal and external communications;
• Supporting the capital and liquidity planning procedures; and
• Notifying and setting of risk tolerance.

When the Basel committee considered the stress tests done before 2007-2008, they concluded that:

• It is crucial to involve the Board and the senior management in stress testing. The Board and the senior management should be involved in stress testing aspects such as choosing scenarios, setting stress testing objectives, analysis of the stress testing results, determining the potential actions, and strategic decision making. During the crisis, banks that had senior management interested in developing a stress test, which eventually affected their decision-making, performed fairly well.
• The approaches of the stress-testing did not give room for the aggregation of different exposures in different parts of a bank. That is, experts from different parts of the bank did not cooperate to produce an enterprise-wide risk view.
• The scenarios chosen in the stress tests were too moderate and were based on a short period of time. The possible correlations between different risk types, products, and markets were ignored. As such, the stress test relied on the historical scenarios and left out risks from new products and positions taken by the banks.
• Some of the risks were not considered comprehensively in the chosen scenarios. For example, counterparty credit risk, risks related to structured products, and product awaiting securitizations were partially considered. Moreover, the effect of the stressed scenario on liquidity was underrated.

Basel Committee Stress Testing Principles

According to the Basel Committee on Banking Supervision’s “Stress Testing Principles” published in December 2017:

1. Stress testing frameworks should incorporate an effective governance structure.

   The stress testing frameworks should involve a governance structure that is clear, documented, and comprehensive. The roles and responsibilities of senior management, oversight bodies, and those concerned with stress testing operations should be clearly stated.

   The stress testing framework should incorporate a collaboration of all required stakeholders and the appropriate communication to stakeholders of the stress testing methodologies, assumptions, scenarios, and results.

2. Stress testing frameworks should have clearly articulated and formally adopted objectives.

   The stress testing frameworks should satisfy the objectives that are documented and approved by the Board of an organization or any other senior governance. The objective should be able to meet the requirements and expectations of the framework of the bank and its general governance structure. The staff mandated to carry out stress testing should know the stress testing framework’s objectives.

3. Stress testing frameworks should capture material and relevant risks and apply sufficiently severe stresses.

   Stress testing should reflect the material and relevant risk determined by a robust risk identification process and key variables within each scenario that is internally consistent. A narrative should be developed explaining a scenario that captures risks, and those risks that are excluded by the scenario should be described clearly and well documented.

4. Stress testing should be utilized as a risk management tool and to convey business decisions.

   Stress testing is typically a forward-looking risk management tool that potentially helps a bank in identifying and monitoring risk. Therefore, stress testing plays a role in the formulation and implementation of strategic and policy objectives. When using stress testing results, banks and authorities should comprehend crucial assumptions and limitations such as the relevance of the scenario, model risks, and risk coverage. Lastly, stress testing as a risk management tool should be done regularly in accordance with a well-developed schedule (except ad hoc stress tests). The frequency of a stress test depends on:

   • The objective of the stress testing framework;
   • The size and complexity of the financial institution; and
   • Changes in the macroeconomic environment.

5. Resources and organizational structures should be adequate to meet the objectives of the stress testing framework.

   Stress testing frameworks should have adequate organizational structures that meet the objectives of the stress test. The governance processes should ensure that the resources for stress testing are adequate, such that these resources have relevant skill sets to implement the framework.

6. Stress tests should be supported by accurate and sufficiently granular data and robust IT systems.

   Stress tests identify risks and produce reliable results if the data used is accurate and complete, and available at an adequately granular level and on time. Banks and authorities should establish a sound data infrastructure which is capable of retrieving, processing, and reporting of information used in stress tests. The data infrastructure should be able to provide adequate quality information to satisfy and objectives of the stress testing framework. Moreover, structures should be put in place to cover any material information deficiencies.

7. Models and methodologies to assess the impacts of scenarios and sensitivities should be fit for purpose.

   The models and methodologies utilized in stress testing should serve the intended purpose. Therefore,

   • There should be an adequate definition of coverage, segmentation, and granularity of the data and the types of risks based on the objectives of the stress test framework. All is done at the modeling stage;
   • The complexity of the models should be relevant to both the objectives of the stress testing and target portfolios being assessed using the models; and
   • The models and the methodologies in a stress test should be adequately justified and documented.

   The model building should be a collaborative task between the different experts. As such, the model builders engage with stakeholders to gain knowledge on the type of risks being modeled and understand the business goals, business catalysts, risk factors, and other business information relevant to the objectives of the stress testing framework.

8. Stress testing models, results, and frameworks should be subject to challenge and regular review.

   Periodic review and challenge of stress testing for the financial institutions and the authorities is important in improving the reliability of the stress testing results, understanding of results’ limitations, identifying the areas that need improvement and ensuring that the results are utilized in accordance with the objectives of the stress testing framework.

9. Stress testing practices and findings should be communicated within and across jurisdictions.

   Communicating the stress testing results to appropriate internal and external stakeholders provides essential perspectives on risks that would be unavailable to an individual institution or authority. Furthermore, disclosure of the stress test results by banks or authorities improves the market discipline and motivates the resilience of the banking sector towards identified stress.

   Banks and authorities who choose to disclose stress testing results should ensure that the method of delivery should make the results understandable while including the limitations and assumptions on which the stress test is based. Clear conveyance of stress test results prevents inappropriate conclusions on the resilience of the banks with different results.

Question 1

Hardik and Simriti compare and contrast stress testing with economic capital and value at risk measures. Which of the following statements regarding differences between the two types of risk measures is most accurate?

A. Stress tests tend to calculate losses from the perspective of the market, while EC/VaR methods compute losses based on an accounting point of view

B. While stress tests focus on unconditional scenarios, EC/VaR methods focus on conditional scenarios

C. While stress tests examine a long period, typically spanning several years, EC models focus on losses at a given point in time, say, the loss in value at the end of year \(t\).

D. Stress tests tend to use cardinal probabilities while EC/VaR methods use ordinal arrangements

The correct answer is C.

Option A is inaccurate: Stress tests tend to calculate losses from the perspective of accounting, while EC/VaR methods compute losses based on a market point of view.

Option B is inaccurate: While stress tests focus on conditional scenarios, EC/VaR methods focus on unconditional scenarios.

Option D is also inaccurate: Stress tests do not focus on probabilities. Instead, they focus on ordinal arrangements like “severe,” “more severe,” and “extremely severe.” EC/VaR methods, on the other hand, focus on cardinal probabilities. For instance, a 95% VaR loss could be interpreted as 5-in-100 events.

Question 2

One of the approaches used to incorporate stress testing in VaR involves the use of stressed inputs. Which of the following statements most accurately represents a genuine disadvantage of relying on risk metrics that incorporate stressed inputs?

A. The metrics are usually more conservative (less aggressive)

B. The metrics are usually less conservative (more aggressive)

C. The capital set aside, as informed by the risk metrics, is likely to be insufficient

D. The risk metrics primarily depend on portfolio composition and are not responsive to emerging risks or current market conditions.

The correct answer is D.

The most common disadvantage of using stressed risk metrics is that they do not respond to current issues in the market. As such, significant shocks in the market can “catch the firm unaware” and result in extensive financial turmoil.

Question 3

Sarah Wayne, FRM, works at Capital Bank, based in the U.S. The bank owns a portfolio of corporate bonds and also has significant equity stakes in several medium-size companies across the United States. She was recently requested to head a risk management department subcommittee tasked with stress testing. The aim is to establish how well prepared the bank is for destabilizing events. Which of the following scenario analysis options would be the best for the purpose at hand?

A. Hypothetical scenario analysis

B. Historical scenario analysis

C. Forward-looking hypothetical scenario analysis and historical scenario analysis

D. Cannot tell based on the given information

The correct answer is C.

Scenario analyses should be dynamic and forward-looking. This implies that historical scenario analysis and forward-looking hypothetical scenario analysis should be combined. Pure historical scenarios can give valuable insights into impact but can underestimate the confluence of events that are yet to occur. What’s more, historical scenario analyses are backward-looking and hence neglect recent developments (risk exposures) and current vulnerabilities of an institution. As such, scenario design should take into account both specific and systematic changes in the present and near future.