FRM Exam Part II · Capital Regulation Before the Global Financial Crisis

Basel II Weaknesses Revealed Before the Crisis

Updated 11 October 2026 · Fact-checked

Basel II tied capital to risk estimates from ratings and internal models. Those estimates looked low in booms and jumped in downturns, so capital was procyclical. Basel II also under-measured trading book and securitization risk and had no leverage or liquidity standards. Banks entered the crisis with too little, too weak capital.

Understand Basel II Weaknesses Revealed Before the Crisis

Basel II linked minimum capital to measured risk. Risk-weighted assets (RWA) came from external ratings under the standardized approach, or from bank estimates of PD, LGD and EAD under the internal ratings-based (IRB) approach. Capital was at least 8% of RWA. That sounds sensible, but it left several weaknesses.

Procyclicality is the first one. Point-in-time PD estimates fall in booms and rise in recessions. So RWA fall when times are good and capital requirements rise when losses are already hitting. Banks that cannot raise capital cheaply in a downturn cut lending, which deepens the downturn. Basel III responded with a countercyclical buffer and conservation buffer.

Reliance on ratings and models is the second. Securitization tranches got low risk weights from agency ratings, and AAA tranches carried very small capital. Ratings were often wrong, and the same exposure could attract very different capital depending on whether it was held as a loan or a tranche. IRB models used short data histories from benign periods. Using the same VaR-style models across banks also encouraged similar behaviour.

Gaps in scope and design is the third. The 1996 market risk rules allowed trading book VaR at 99%, 10-day, with no stress calibration. It did not capture default and migration risk of credit products, nor illiquidity of securitization positions held for trading. Positions could be kept in the trading book to get lower capital. Off-balance-sheet vehicles (conduits and SIVs) held assets with little capital but came back on balance sheet with liquidity support.

Missing standards: Basel II had no leverage ratio, so low risk weights allowed very high leverage. It had no global liquidity standard, so banks relied on short-term wholesale funding. The quality of capital was weak too, with hybrid instruments counting as Tier 1 and little common equity required. Basel 2.5 (2009) was the quick fix. It added stressed VaR, an incremental risk charge (IRC) for default and migration risk, a comprehensive risk measure for correlation trading, and much higher charges for resecuritizations. Basel III then added the rest.

Key formulas to remember

Basel II minimum capital ratio: Total capital ÷ (Credit RWA + 12.5 × (Market risk capital + Operational risk capital)) ≥ 8%; Market and operational capital charges are converted to RWA by multiplying by 12.5 (the reciprocal of 8%).
Basel 2.5 market risk capital (internal models): VaR + stressed VaR + IRC + CRM (for correlation trading), each with multipliers; Stressed VaR uses a 12-month period of significant stress. IRC is a 99.9%, one-year measure of default and migration risk.
Unweighted leverage ratio (Basel III fix): Tier 1 capital ÷ Total exposure ≥ 3%; Non-risk-based backstop. Basel II had no such measure.
Procyclicality mechanism: Boom: lower PD → lower RWA → lower capital. Bust: higher PD → higher RWA → higher capital; Stated as direction of effect, not a fixed number. It is strongest with point-in-time ratings.

How to solve Basel II Weaknesses Revealed Before the Crisis questions

Most questions give a scenario and ask which weakness it shows, or which reform fixes it. Use this routine.

1Read the scenario and identify the exposure: banking book loan, trading book position, securitization tranche, off-balance-sheet vehicle, or funding.
2Decide what drove the capital number: external rating, internal PD/LGD estimates, or VaR.
3Check the timing: does the requirement fall in good times and rise in bad times? If so, it is procyclicality.
4Check for a gap: no leverage limit, no liquidity standard, low-quality capital, or regulatory arbitrage between books.
5Match the weakness to the fix: stressed VaR, IRC, countercyclical buffer, leverage ratio, LCR and NSFR, higher common equity.
6Test each option for exact wording. Reject options that overstate, such as saying Basel II had no credit risk capital.
7Choose the option that names the right mechanism, not just a plausible symptom.

Quickest way: Weakness-to-fix matching

When to use it: Use when the question asks which reform addresses a named weakness.

Procyclicality: countercyclical buffer, conservation buffer, through-the-cycle thinking.
Trading book tail and stress gaps: stressed VaR.
Default and migration risk in trading credit: IRC.
Securitization and ratings reliance: higher risk weights for resecuritizations, due diligence, less mechanical rating use.
Excess leverage: leverage ratio.
Funding fragility: LCR and NSFR.
Poor capital quality: higher common equity and stricter Tier 1 criteria.

Common mistakes in Basel II Weaknesses Revealed Before the Crisis

Saying Basel II procyclicality means capital requirements rise in booms.
Students confuse the direction of risk with the direction of measured risk.
Fix: Measured PDs fall in booms, so RWA and capital fall. The reverse happens in downturns.
Treating Basel 2.5 and Basel III as the same thing.
Both came after the crisis and both raised capital.
Fix: Basel 2.5 mainly patched the trading book and securitization rules in 2009. Basel III added the buffers, leverage ratio, liquidity ratios and stricter capital definition.
Claiming Basel II had a leverage ratio or liquidity ratio.
Students mix up the Basel II and Basel III frameworks.
Fix: Basel II was purely risk-weighted for capital and had no global leverage or liquidity standard.
Blaming only rating agencies.
The ratings story is the easiest to remember.
Fix: Rating reliance was one factor. Capital arbitrage, short data histories, off-balance-sheet vehicles and weak capital quality also mattered.
Saying stressed VaR replaced VaR.
The names suggest a substitute.
Fix: Stressed VaR is added to current VaR. Both are in the capital charge.
Assuming IRB models are procyclical by design flaw alone.
Students ignore the role of rating philosophy.
Fix: Point-in-time ratings increase procyclicality. Through-the-cycle ratings reduce it. The effect depends on calibration.

Worked examples

Example 1

A bank uses IRB with point-in-time PDs. During a long boom, its average PD falls from 2% to 1%, and exposures are unchanged. Everything else being equal, what happens to credit capital, and what does it show?

Show the solution

PD enters the IRB risk-weight formula with a positive relationship: lower PD gives a lower risk weight.
A lower risk weight gives lower RWA for the same exposure.
Minimum capital is 8% of RWA, so required capital falls.
Capital requirements fall in good times. If PDs jump in a downturn, capital needed rises sharply when losses are rising.

Answer: Required capital falls in the boom. This shows procyclicality: requirements fall in good times and rise in bad times, which can force deleveraging in a downturn.

Example 2

A bank has credit RWA of $50 billion, market risk capital of $2 billion and operational risk capital of $1 billion under Basel II. What is the minimum total capital at 8%?

Show the solution

Convert market risk capital to RWA: 12.5 × 2 = $25 billion.
Convert operational risk capital to RWA: 12.5 × 1 = $12.5 billion.
Total RWA = 50 + 25 + 12.5 = $87.5 billion.
Minimum capital = 8% × 87.5 = $7 billion.
Check: 8% × 50 = 4, plus 2, plus 1 = $7 billion.

Answer: Minimum total capital is $7 billion.

Exam tips

Questions often ask for the weakness behind a scenario. Name the mechanism, not just the symptom.
Know the Basel 2.5 components: stressed VaR, IRC, CRM and higher securitization charges.
Remember the direction of procyclicality: capital falls in booms and rises in busts.
Do the 12.5 conversion carefully when a numerical question mixes capital charges and RWA.
Eliminate options that attribute Basel III features, such as leverage ratio or LCR, to Basel II.

Practice questions from Capital Regulation Before the Global Financial Crisis

Basel II Weaknesses Revealed Before the Crisis: frequently asked questions

Why did Basel II fail in the financial crisis?

It allowed low capital against securitized and trading positions, relied on ratings and short-history models, and had no leverage or liquidity standards. Capital quality was also weak. Banks had too little loss-absorbing equity when losses hit.

What is procyclicality in Basel II?

It is the tendency for risk-based capital requirements to fall in booms and rise in downturns. This happens because measured PDs and RWA move with the cycle. It can push banks to cut lending when the economy is weak.

What did Basel 2.5 change?

Basel 2.5 raised trading book capital. It added stressed VaR, an incremental risk charge, a comprehensive risk measure for correlation trading, and higher charges for resecuritizations.

Did Basel II have leverage and liquidity rules?

No. Basel II had no global leverage ratio and no global liquidity standard. Basel III introduced the leverage ratio, the LCR and the NSFR.