Welcome to the Fundamental Review of the Trading Book (FRTB)!
Hello there! Today, we are diving into one of the most important updates in the world of market risk: the Fundamental Review of the Trading Book, or FRTB. If you’ve been studying Basel regulations, you know that rules evolve. Think of FRTB as "Market Risk 2.0." It was designed by the Basel Committee to fix the weaknesses exposed during the 2008 financial crisis. Don’t worry if this seems like a lot of technical jargon at first—we’re going to break it down piece by piece until it feels like second nature!
Why is this important? Before FRTB, banks found "loopholes" to hold less capital by moving assets between different "books." FRTB closes those doors and ensures banks have enough of a cushion to survive extreme market crashes.
Quick Tip: In the FRM exam, focus on the "why" and "how" the rules changed, rather than just memorizing every single number.
1. The Boundary: Trading Book vs. Banking Book
One of the biggest problems in the past was arbitrage. Banks would move instruments between the Banking Book (meant for long-term holdings) and the Trading Book (meant for active trading) to take advantage of lower capital requirements. FRTB creates a much stricter wall between them.
The New Rules of the Boundary
- Strict Evidence: To put something in the trading book, a bank must prove there is intent to trade.
- Approval for Switches: Moving an asset from one book to another is now very difficult and requires supervisor approval. If a bank does switch an asset, they generally aren't allowed to benefit from a lower capital charge because of it (the "no capital benefit" rule).
Analogy: Imagine you have two closets—one for daily clothes and one for winter storage. If the rules say you pay "tax" on daily clothes but not storage, you’d try to cram everything into storage. FRTB is like a strict inspector who checks if you’re actually wearing those "storage" clothes every day!
Key Takeaway
The Boundary is now more rigid to prevent regulatory arbitrage, ensuring that risk is measured consistently based on how the asset is actually managed.
2. The Standardized Approach (SA)
Even if a bank is allowed to use its own complex models, it must still calculate its risk using the Standardized Approach (SA). This acts as a fallback and a benchmark. The SA in FRTB is much more "risk-sensitive" than the old versions.
The Three Components of SA
The total capital charge under the Standardized Approach is the sum of three parts:
- Sensitivities-Based Method (SBM): This looks at how much the portfolio value changes when market factors (like interest rates or equity prices) move slightly. It includes three main risks: Delta (price change), Vega (volatility change), and Curvature (non-linear risk).
- Default Risk Charge (DRC): This captures the risk that an issuer of a bond or stock in the trading book might go bankrupt suddenly (jump-to-default risk).
- Residual Risk Add-on (RRAO): This is a "catch-all" charge for exotic risks that aren't captured by the first two. If it’s weird and complex, it gets taxed here!
Memory Aid: Remember "D-V-C" for the SBM—Delta, Vega, and Curvature. These are the "Big Three" of sensitivity risk.
Key Takeaway
The Standardized Approach is a more granular, three-part calculation that ensures a consistent "floor" for capital across all banks.
3. Internal Models Approach (IMA): The Move to Expected Shortfall
This is arguably the biggest change in FRTB. For years, banks used Value at Risk (VaR). However, VaR has a major flaw: it doesn't tell you what happens in the "tail" (the absolute worst-case scenarios).
Goodbye VaR, Hello Expected Shortfall (ES)!
Under FRTB, the 99% VaR is replaced by 97.5% Expected Shortfall (ES). While VaR asks, "What is the minimum I could lose in the worst 1% of cases?", ES asks, "On average, how much will I lose given that I am in that worst-case zone?"
The Formula: \( ES = \frac{1}{1-\alpha} \int_{\alpha}^{1} VaR_u du \)
Don't let the integral scare you! It just means "the average of all VaRs beyond the threshold."
Liquidity Horizons
In the old days, we assumed we could sell anything in 10 days. The 2008 crisis showed that was false. FRTB introduces varying liquidity horizons (10, 20, 40, 60, and 120 days). If an asset is harder to sell (like a complex credit derivative), the bank must hold more capital to account for the longer time it takes to exit the position.
Did you know? This shift means that capital requirements are generally higher under FRTB than under the old Basel rules, especially for illiquid assets.
Key Takeaway
The Internal Models Approach moves from VaR to Expected Shortfall to better capture tail risk and uses liquidity horizons to reflect how long it actually takes to sell an asset during a crisis.
4. Model Approval and the "Report Card"
Under FRTB, a bank doesn't just get "Internal Model" status for the whole bank. It is granted desk-by-desk. If the "Equities Desk" has a great model but the "Fixed Income Desk" has a bad one, only the Equities Desk gets to use it.
How is a model judged?
- Backtesting: Comparing predicted losses to actual losses. If the model fails too many times (exceptions), it loses its license.
- P&L Attribution (PLA): This checks if the "Risk P&L" (what the model predicted) matches the "Hypothetical P&L" (what actually happened). If they don't move together, the model is considered inaccurate.
Non-Modellable Risk Factors (NMRFs)
If a bank wants to use a risk factor in its model (like a specific stock's volatility), it must prove there is enough data. If the data is "stale" or non-existent, that factor is labeled an NMRF. Banks must pay a separate, very high capital charge for these factors. This encourages banks to use high-quality, transparent data.
Key Takeaway
Model approval is now much stricter, applied at the trading desk level, and relies on P&L Attribution and Backtesting to ensure the models actually work.
5. Summary and Quick Review
We’ve covered a lot! Let’s wrap it up with the most important points you need to remember for your exam.
Quick Review Box:
• The Boundary: Stricter rules to stop banks from moving assets to save capital.
• Standardized Approach (SA): Sensitivities (Delta/Vega/Curvature), Default Risk, and Residual Risk.
• Internal Models (IMA): Shift from 99% VaR to 97.5% Expected Shortfall (ES).
• Liquidity: Different time horizons for different assets (10 to 120 days).
• NMRFs: High capital charges for risks with poor data.
• Approval: Granted at the Desk Level, not the Bank Level.
Common Mistake to Avoid: Students often think ES is always higher than VaR because of the confidence level. Remember, while the confidence level moved from 99% to 97.5%, ES is an average of the tail, whereas VaR is just a single point. ES is generally more conservative and leads to higher capital requirements.
Great job getting through this! FRTB is complex, but by focusing on the transition from VaR to ES and the tightening of the rules around the trading book boundary, you are well on your way to mastering this chapter. Keep pushing forward—you’ve got this!