CA-14.7 CA-14.7 Stress Testing
CA-14.7.1
Banks that use the internal models approach for calculating market risk capital requirements must have in place a rigorous and comprehensive stress testing programme. Stress testing to identify events or influences that could greatly impact the bank is a key component of a bank's assessment of its capital position.
Apr 08CA-14.7.2
Banks' stress scenarios need to cover a range of factors that can create extraordinary losses or gains in trading portfolios, or make the control of risk in those portfolios very difficult. These factors include low-probability events in all major types of risks, including the various components of market, credit and operational risks. Stress scenarios need to shed light on the impact of such events on positions that display both linear and non-linear characteristics (i.e.,
options and instruments that haveoption -like characteristics).Apr 08CA-14.7.3
Banks' stress tests should be both of a quantitative and qualitative nature, incorporating both market risk and liquidity aspects of market disturbances. Quantitative criteria should identify plausible stress scenarios to which banks could be exposed. Qualitative criteria should emphasise that two major goals of stress testing are to evaluate the capacity of the bank's capital to absorb potential large losses and to identify steps the bank can take to reduce its risk and conserve capital. This assessment is integral to setting and evaluating the bank's management strategy and the results of stress testing should be routinely communicated to senior management and, periodically, to the bank's board of directors.
Apr 08CA-14.7.4
Banks must combine the use of stress scenarios as advised under (a), (b) and (c) below by the CBB, with stress tests developed by the banks themselves to reflect their specific risk characteristics. The CBB may ask banks to provide information on stress testing in three broad areas, as discussed below:
(a) Scenarios requiring no simulation by the bank:
Banks must have information on the largest losses experienced during the reporting period available for review by the CBB. This loss information will be compared with the level of capital that results from a bank's internal measurement system. For example, it could provide the CBB with a picture of how many days of peak day losses would have been covered by a givenvalue-at-risk estimate.(b) Scenarios requiring simulation by the bank:
Banks must subject their portfolios to a series of simulated stress scenarios and provide the CBB with the results. These scenarios could include testing the current portfolio against past periods of significant disturbance, for example, the 9/11 attacks on the USA, the 1987 equity market crash, the Exchange Rate Mechanism crises of 1992 and 1993 or the fall in the international bond markets in the first quarter of 1994, the 1998 Russian financial crisis, the 2000 bursting of the technology stock bubble or the 2007/2008 sub-prime crisis, incorporating both the large price movements and the sharp reduction in liquidity associated with these events. A second type of scenario would evaluate the sensitivity of the bank's market riskexposure to changes in the assumptions about volatilities and correlations. Applying this test would require an evaluation of the historical range of variation for volatilities and correlations and evaluation of the bank's current positions against the extreme values of the historical range. Due consideration should be given to the sharp variation that, at times, has occurred in a matter of days in periods of significant market disturbance. For example, the above-mentioned situations involved correlations within risk factors approaching the extreme values of 1 and -1 for several days at the height of the disturbance.(c) Scenarios developed by the bank to capture the specific characteristics of its portfolio:
In addition to the general scenarios prescribed by the CBB under (a) and (b) above, each bank must also develop its own stress scenarios which it identifies as most adverse based on the characteristics of its portfolio (e.g.. any significant political or economic developments that may result in a sharp move in oil prices). Banks must provide the CBB with a description of the methodology used to identify and carry out the scenarios as well as with a description of the results derived from these stress tests.Amended: January 2012
Amended: April 2011
Apr 08CA-14.7.5
Once a stress scenario has been identified, it should be used for conducting stress tests at least once every quarter, as long as the scenario continues to be relevant to the bank's portfolio.
Apr 08CA-14.7.6
The results of all stress tests should be reviewed by senior management within 15 days from the time they are available, and should be promptly reflected in the policies and limits set by management and the board of directors. Moreover, if the testing reveals particular vulnerability to a given set of circumstances, the CBB would expect the bank to take prompt steps to manage those risks appropriately (e.g., by
hedging against that outcome or reducing the size of itsexposures ).Apr 08CA-14.7.7
Banks must conduct, at least weekly, a set of pre-determined stress-tests for the correlation trading portfolio encompassing shocks to default rates, recovery rates, credit spreads, and correlations. Appendix CA-19 provides guidance on the stress testing that must be undertaken to satisfy this requirement.
Added: January 2012