The basic measurement model used to assess market risk is Value-at-Risk (VaR), which provides a forecast of the maximum loss that can be incurred by trading portfolios in a one-day horizon, with a 99% probability, stemming from fluctuations in equity prices, interest rates, foreign exchange rates and commodity prices. In addition, for certain positions, other risks also need to be considered, such as credit spread risk, basis risk, volatility and correlation risk. The VaR is calculated by using a historical period of 2 years for the observation of the risk factors.
Currently, BBVA, S.A. and BBVA Bancomer have been authorized by the Bank of Spain to use their internal model to determine capital requirements deriving from risk positions in their trading book, which jointly accounts for 80-90% of the Group’s trading book market risk. BBVA is in the process of incorporating the new regulatory capital charges to comply with the most recent guidelines of the regulators.
The market risk limits model currently in force consists of a system of VaR (Value at Risk) and economic capital limits and VaR sub-limits, as well as stop-loss limits for each of the Group’s business units. The global limits are proposed by the Risk Area and approved by the Executive Committee on an annual basis, once they have been submitted to the Board’s Risk Committee.
This limits structure is developed by identifying specific risks by type, trading activity and trading desk. The market risk units maintain consistency between the limits. This system of limits is supplemented by measures of the impact of extreme market movements on risk positions. The Group is currently performing stress testing on historical and economic crisis scenarios, as well as impact analyses on the income statement in plausible but unlikely economic crisis scenarios, drawn up by its Economic Research Department.
In order to assess business unit performance over the year, the accrual of negative earnings is linked to the reduction of the VaR limits that have been set. The control structure in place is supplemented by limits on loss and a system of alert signals to anticipate the effects of adverse situations in terms of risk and/or result. All the tasks associated with stress testing, methodologies, scenarios of market variables and reports are undertaken in coordination with the Group’s various Risk Areas.
Finally, the market risk measurement model includes backtesting or ex-post comparison which helps to refine the accuracy of the risk measurements by comparing day-on-day results with their corresponding VaR measurements.