Stress Tests & Scenario Analysis

Stress tests assess a financial institution's resilience against extreme but plausible single events, such as a 200 basis point interest rate shock or a 35% equity market crash. Scenario analysis examines coherent future states with multiple simultaneous risk factors over a longer time horizon. Both instruments are complementary: stress tests provide quantitative resilience thresholds while scenario analysis enables strategic decision-making. The EBA Guidelines 2018‑04 explicitly require both methods as part of the ICAAP process.

Banks must conduct stress tests under multiple regulatory frameworks. The EBA Guidelines require sensitivity and scenario stress tests with anchor scenarios integrated into ICAAP/ILAAP processes. The Basel Framework mandates Expected Shortfall under stress periods for market risk, Downturn-LGD for credit risk, and LCR/NSFR under stress for liquidity risk. In Germany, MaRisk AT 4.3.2 requires integration into the risk-bearing capacity concept. The 2026 ECB stress test introduces inverse methodology: banks must develop geopolitical crisis scenarios leading to a predefined 300 basis point CET1 capital loss.

A reverse stress test works backward to identify scenarios that would cause a bank to breach regulatory capital ratios or face insolvency. It is mandatory for banks under ICAAP and for insurers under the ORSA process. The 2026 ECB stress test uses an inverse format for the first time: banks receive a target capital loss of 300 basis points CET1 and must construct plausible geopolitical scenarios that trigger this loss. Methodologies include reverse engineering, Bayesian networks, and optimization algorithms such as genetic algorithms or simulated annealing.

The EBA stress test includes a baseline and an adverse scenario over a three-year horizon. Banks calculate losses, revenues, and resulting capital ratios under both scenarios. The EBA prescribes macroeconomic scenarios and methodology while institutions provide bottom-up calculations at individual position level. The process spans approximately nine months from scenario delivery through data collection and calculation to results publication. In 2026, the ECB additionally tests geopolitical risks thematically using the new inverse methodology.

Climate stress tests assess the impact of physical risks (extreme weather, sea level rise) and transition risks (carbon pricing, technology shifts) on financial institutions. Key frameworks include NGFS scenarios (Orderly/Disorderly Transition, Hot House World), IEA pathways (Net Zero 2050, Stated Policies), and IPCC climate pathways. The ECB requires integration of climate scenarios into existing stress test frameworks with time horizons of 2030 and 2050 and CO2 price paths ranging from EUR 50 to EUR 200 per tonne.

An effective stress test framework comprises four pillars: First, governance with clear role allocation and linkage to risk appetite. Second, scenario design with systematic risk factor identification, calibration, and consistency checks. Third, modeling with defined granularity, validated methods, and documented limitations. Fourth, operationalization with IT infrastructure, process integration, thresholds, and escalation procedures. The proportionality principle ensures the effort matches the institution's size and complexity.

ADVISORI supports the full stress testing lifecycle: gap analysis of existing processes, methodology development for sensitivity and scenario stress tests, IT system integration for data management and computation, regulatory documentation, and staff training. Typical project scope ranges from single risk-type stress tests to integrated multi-risk frameworks. For the 2026 ECB stress test, we help banks develop inverse geopolitical scenarios and meet the new methodology requirements within the regulatory timeline.