Stress Testing Counterparty Credit Risk Exposures

Credit → Counterparty Analysis
| 2025-11-13 23:29:27

Introduction to Stress Testing Counterparty Credit Risk Exposures

Foundations and Importance of Stress Testing for Counterparty Credit Risk

Overview

  • Stress testing is crucial to assess resilience of exposures under extreme market conditions.
  • It helps identify directional sensitivities and concentration risks in counterparty portfolios.
  • We will explore methodologies, key drivers, and results interpretation in the following slides.
  • Key insights include multifactor stress frameworks and the role of wrong-way risk.

Key Concepts and Drivers in Stress Testing CCR

Understanding the Mechanics and Risk Factors in CCR Stress Testing

Main Points

  • Stress tests consider exposures to principal market risk factors: interest rates, FX, equities, credit spreads, commodities.
  • Multifactor scenarios simulate severe macroeconomic or liquidity shocks plus market impacts of large position liquidations.
  • Wrong-way risk, the correlation of counterparty default likelihood and exposure, complicates risk capture.
  • Scenario analysis complements traditional risk metrics like VaR, improving capital allocation and risk management.

Graphical Analysis – Stress Testing CCR Exposures: Multifactor Scenario Impact

Visualizing Exposure Changes Under Multifactor Stress Scenarios

Context and Interpretation

  • This layered chart presents hypothetical changes in maximum and minimum counterparty exposures alongside credit spread impacts over three months under stress.
  • Shows potential widening of exposure ranges and concurrent credit spread increases, indicating elevated risk.
  • Highlights the importance of monitoring joint movements in exposure and credit quality.
  • Supports assessing tail risk and informs stress scenario design.
Figure: Exposure and Credit Spread Variation Under Stress
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    {"Month":"Jan","exposure_max":15,"exposure_min":5,"credit_spread":2},
    {"Month":"Feb","exposure_max":18,"exposure_min":6,"credit_spread":3},
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Analytical Summary & Tabular Data of CCR Stress Metrics

Interpreting Key Quantitative Inputs and Risk Metrics

Key Discussion Points

  • Stress testing evaluates exposures, potential future exposures (PFE), and credit valuation adjustments (CVA) under stressed conditions.
  • Metrics help quantify tail risk not captured by traditional mark-to-market views.
  • Assumptions often include correlations, default probabilities, and loss given default estimates; results are scenario and model dependent.
  • Limitations include model risk and challenges incorporating wrong-way risk fully.

Illustrative Stress Testing Metrics Table

Sample data reflecting counterparty exposure metrics under baseline and stress scenarios.

CounterpartyBaseline Exposure (M)Stressed Exposure (M)Stressed CVA (M)
Counterparty A50753.5
Counterparty B30452.1
Counterparty C40602.9
Counterparty D20351.7

Graphical Analysis – Stress Testing CCR: Exposure Distribution by Counterparty Type

Context and Interpretation

  • This bar chart depicts stressed exposures segmented by counterparty categories such as financial institutions, corporates, sovereigns, and others.
  • Highlights concentration risks within financial institutions, a critical factor for systemic risk assessments.
  • Enables risk managers to prioritize monitoring and capital allocation strategies.
  • Supports regulatory and internal risk management perspectives on exposure diversification.
Figure: Stressed Exposure Distribution Across Counterparty Types
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      {"Category": "Financial Institutions", "Value": 120},
      {"Category": "Corporates", "Value": 80},
      {"Category": "Sovereigns", "Value": 40},
      {"Category": "Others", "Value": 25}
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      "title": "Exposure Value"
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Code Example: Python for CCR Stress Testing Calculation

Code Description

This Python script calculates the Credit Valuation Adjustment (CVA) under a stress scenario incorporating expected exposure and default probabilities.

import numpy as np

def calculate_cva(lgd, expected_exposures, default_probs):
    """Calculate CVA using expected exposures and default probabilities."""
    cva = np.sum(lgd * expected_exposures * default_probs)
    return cva

# Inputs
lgd = 0.6  # Loss Given Default
expected_exposures = np.array([50, 45, 40, 35])  # Expected exposures over time
# Default probabilities reflecting stressed conditions
default_probs = np.array([0.01, 0.02, 0.015, 0.025])

cva_value = calculate_cva(lgd, expected_exposures, default_probs)
print(f"Calculated CVA under stress: {cva_value:.2f} million")

Conclusion and Next Steps in CCR Stress Testing

Synthesis and Path Forward for Effective CCR Stress Testing

  • Stress testing CCR is essential to detect vulnerabilities in counterparty portfolios under extreme but plausible scenarios.
  • Multifactor and wrong-way risk considerations enhance the relevance of stress tests.
  • Next steps include integrating results into risk appetite frameworks and capital planning.
  • Continued model validation and scenario updating are crucial for maintaining effectiveness.
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