STRESS TESTING
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Transcript STRESS TESTING
Stress Testing
Presented to The Institute of Banking (IOB)
Riyadh, 23rd March 2011
Presented by: Syed Faraz Husain, Group Risk Management, NCB
Purpose and Use of Stress Testing
Stress Tests are used to support the statistical tools such as Value-at-Risk (VaR) to gauge
the impact of the ‘tail risks’.
Stress Tests are non-statistical tools where risk factors are stressed to assess their impact
on the bank. Hence, stress testing complements the VaR / Unexpected Loss
methodologies to assess the kind of losses that may occur if the markets are very
stressed and start behaving abnormally ('tail risk').
Stress Tests are used by Senior Management and the Board to ensure that the Bank has
sufficient Capital to withstand such losses should they ever occur.
Stress Tests serve as an input to test the Risk Appetite of the Bank – e.g. if any particular
risk is unwanted and, therefore, should be avoided
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Stressing Models vs. Scenario Analysis
Stressing Models
Scenario Analysis
Methods
Methods
o Push factor analysis – A factor or factors are
deliberately pushed to extreme and the
impact on the portfolio is measured
o Stylized Scenarios – based on industry
standards such as those defined by the
Derivatives Policy Group or by Regulators
o Maximum loss optimization - Identifies risk
factors that have the greatest potential
impact on the portfolio and moving to
protect against those factors
o Actual extreme events – uses past events
such as market crash of 1987, technology
bubble of 1990 etc.
o Worst Case scenario – All risk factors are
pushed to their worst cases
o Hypothetical events – that are based on
events that have not occurred but may
occur in future
Challenges
Challenges
o Incorrect inputs and assumptions and user
bias
o Inability to measure by-products of major
factor movements or include effects of
simultaneous adverse movements
o Inaccurately constructed risk models
o undue reliance on models
o User specification of the movements and
their correlations
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Developments in Stress Testing & Impact of 2008 Financial Crisis
Stress Testing importance has been magnified
Stress testing methodologies have been developed and formally documented as a policy
In some cases results of past stress tests validated and in other areas assumptions used
have been revisited
Results of stress tests are now being presented in a more comprehensive manner at the
entity level to the Senior Management and the Board
Actions are being taken to manage risks highlighted through stress tests
Results of Stress testing on capital are being presented and discussed with SAMA as
part of the ICAAP process
SAMA endorsed the “Principles for sound stress testing practices and supervision”
issued by The Basel Committee on Banking Supervision in 2009
Frequency of stress tests and reviewing underlying assumptions increased
Public disclosures could be mandated in future by International Financial Reporting
Standards or Regulators
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