CMA Final · Risk Management in Banking and Insurance
Credit Risk Management: formula sheet
Key formulas
- Expected loss
- EL = PD × LGD × EAD
- PD is probability of default, LGD is loss given default, EAD is exposure at default. Treat it as an introduction here; the detailed measurement is a separate topic.
- Loss given default
- LGD = 1 − Recovery rate
- Both are expressed as a proportion of exposure at default.
- Concentration share
- Concentration (%) = Exposure to one borrower, group or sector ÷ Total exposure × 100
- Use it to spot concentration. Compare the result against the bank's internal limits and regulatory exposure norms.
- Expected loss
- EL = PD × LGD × EAD
- Used to price loans and set provisions; PD is probability of default, LGD is loss given default, EAD is exposure at default.
- Exposure limit (percentage of capital)
- Maximum exposure = Limit % × Capital base
- Use the capital base specified by the regulator or bank policy for the limit in the question; do not assume the percentage unless given.
- Headroom under a limit
- Headroom = Limit − Existing exposure
- A new proposal is within limit only if proposed exposure ≤ headroom.
- Portfolio share of a sector
- Sector share = Sector exposure ÷ Total portfolio × 100
- Compare with the internal sector cap to test concentration.
- Altman Z-score (original, listed manufacturing companies)
- Z = 1.2×X1 + 1.4×X2 + 3.3×X3 + 0.6×X4 + 1.0×X5
- X1 = working capital ÷ total assets; X2 = retained earnings ÷ total assets; X3 = EBIT ÷ total assets; X4 = market value of equity ÷ book value of total liabilities; X5 = sales ÷ total assets.
- Altman Z-score zones (original model)
- Z > 2.99 safe; 1.81 to 2.99 grey; Z < 1.81 distress
- Cut-offs differ for the Z′ (private firms) and Z″ (non-manufacturers) versions. Say which model you use.
- Transition matrix property
- Σ of probabilities in each row = 100%
- Row = current grade; column = grade at end of period. Default is usually an absorbing state.
- Probability of default from a matrix
- PD (1 year) = value in the row of the current grade, column 'Default'
- For two years, multiply the matrix by itself, assuming migrations are independent across years.
- Expected loss
- EL = PD × LGD × EAD
- Links the rating (which gives PD) to the loss estimate.
- Debt service coverage ratio
- DSCR = (PAT + depreciation + interest on term loan) ÷ (interest + instalment of term loan)
- Common capacity test. Banks usually look for a figure comfortably above 1.
- Expected loss
- EL = PD × LGD × EAD
- Use PD and LGD as decimals. EL is in rupees. All three must refer to the same horizon.
- Loss given default
- LGD = 1 − Recovery rate
- Recovery rate is net of workout costs if the question says so.
- Exposure at default
- EAD = Drawn amount + CCF × Undrawn commitment
- CCF is the credit conversion factor, given in the question.
- Portfolio expected loss
- EL(portfolio) = Σ EL of each exposure
- Expected losses add up simply, whatever the correlation.
- Unexpected loss, single exposure with fixed LGD and EAD
- UL = EAD × LGD × √[PD × (1 − PD)]
- Assumes LGD is certain and default is a yes/no event. Sound only under this simplification.
- Credit VaR
- Credit VaR = Loss at chosen confidence level − EL
- Some texts define credit VaR as the loss quantile itself. Follow the definition in the question.
- Net loss rate or EL rate
- EL rate = EL ÷ EAD = PD × LGD
- Useful to compare pricing across loans.
- Risk-weighted asset (funded exposure)
- RWA = Exposure (net of eligible provisions/collateral, where allowed) × Risk weight
- Use the exposure value the question gives. Apply the risk weight as a percentage.
- Off-balance sheet exposure
- Credit equivalent = Notional amount × Credit conversion factor (CCF); RWA = Credit equivalent × Risk weight
- Convert first, then apply the counterparty's risk weight.
- Capital adequacy ratio (CRAR)
- CRAR = Eligible capital ÷ Total RWA × 100
- Total RWA should include credit, market and operational risk RWA when given.
- Tier 1 ratio
- Tier 1 ratio = Tier 1 capital ÷ Total RWA × 100
- Tier 1 = Common Equity Tier 1 + Additional Tier 1.
- Minimum capital required
- Required capital = Total RWA × Minimum CRAR %
- Compare with actual capital to find surplus or shortfall.
- Capital for operational/market risk to RWA
- RWA equivalent = Capital charge × (100 ÷ Minimum CRAR %)
- Use the minimum ratio the question states, for example ×11.11 at 9%.
- IRB inputs
- Expected loss = PD × LGD × EAD
- IRB risk weights are driven by PD, LGD and EAD (and maturity). Foundation: own PD. Advanced: own PD, LGD, EAD.
- Net exposure after collateral (comprehensive approach)
- E* = max{0, E × (1 + He) − C × (1 − Hc − Hfx)}
- E = exposure, He = haircut on exposure, C = collateral value, Hc = haircut on collateral, Hfx = currency mismatch haircut. Capital is then computed on E*.
- Simple netting of loans and deposits
- Net exposure = Loan outstanding − Eligible deposit set off
- Applies only when there is a legally enforceable netting right. Floor at zero.
- Guarantee substitution
- Covered portion takes the guarantor's risk weight; uncovered portion keeps the borrower's risk weight
- Applies for eligible guarantees. Risk-weighted assets = covered × guarantor RW + uncovered × borrower RW.
- Risk-weighted assets and capital
- RWA = Exposure × Risk weight; Capital required = RWA × minimum capital ratio
- Use the ratio given in the question. Do not assume a figure.
- Credit default swap payout
- Payout = Notional × (1 − Recovery rate)
- Applies on a credit event under cash settlement. Annual premium = Spread × Notional.
- Expected loss
- EL = PD × LGD × EAD
- Collateral and guarantees reduce LGD or EAD, and so reduce EL.
- NPA test (term loans)
- Overdue > 90 days → NPA
- Interest or principal overdue for more than 90 days. Standard assets are not overdue beyond this.
- Sub-standard asset
- NPA for ≤ 12 months
- Secured sub-standard asset: provision 15% of outstanding. If the exposure is unsecured, the rate is 25% (15% + 10% additional). An exposure is unsecured where the realisable value of the security, as assessed by the bank, approved valuers or RBI's inspecting officers, is not more than 10% ab initio (from the start) of the outstanding.
- Doubtful asset
- Sub-standard for 12 months
- Secured portion: 25% (up to 1 year), 40% (1-3 years), 100% (over 3 years). Unsecured portion: 100%.
- Loss asset
- Provision = 100% of outstanding
- Applies to the amount not written off.
- Unsecured sub-standard exposure
- Provision = 25% of outstanding
- Where the realisable value of security is not more than 10% ab initio of the outstanding (as assessed by the bank, approved valuers or RBI), the sub-standard rate is 25%, not 15%.
- Doubtful provision
- Provision = 100% × unsecured portion + rate × secured portion
- Unsecured portion = outstanding − realisable value of security.
- Net NPA
- Net NPA = Gross NPA − provisions held
- Net NPA ratio = Net NPA ÷ Net advances.
- Gross NPA ratio
- Gross NPA ÷ Gross advances × 100
- Key measure of asset quality.
- Provision Coverage Ratio
- PCR = Provisions held against NPAs ÷ Gross NPA × 100
- Shows how much of NPAs is already covered.
- Standard asset provision
- Provision = standard asset rate for the sector × outstanding
- Standard asset provision rates vary by sector: 0.25% for direct advances to agriculture and SMEs, 0.40% for other (general) standard advances, 0.75% for commercial real estate - residential housing (CRE-RH), and 1% for commercial real estate (CRE). Use the rate given in the question.
Quick revision
- Credit risk is the risk of loss when a borrower or counterparty fails to meet its obligation on time.
- Components include default risk, exposure risk, recovery risk, concentration risk and counterparty risk.
- Expected loss = PD × LGD × EAD.
- PD is the likelihood of default over a stated period, usually one year.
- LGD is the share of exposure lost after recoveries; recovery rate = 1 − LGD.
- EAD is the amount outstanding at the time of default, including expected drawdown of undrawn limits.
- Expected loss is covered by pricing and provisions; unexpected loss is covered by capital.
- Risk-weighted assets = exposure × risk weight; capital ratio = capital ÷ RWA.
- Collateral, guarantees and netting reduce exposure; credit derivatives and securitisation transfer risk.
- A credit policy sets limits, delegation of powers, pricing and monitoring rules.
- Credit rating gives an opinion on the likelihood of timely repayment.
- Asset classification moves a loan from standard to NPA stages based on overdue period; provisions rise as the asset worsens.
Common mistakes
- Treating credit risk and counterparty risk as the same thing. Fix: Counterparty risk is a subset tied to trades and contracts where the exposure value changes before settlement. Default risk on a loan is about the borrower repaying principal and interest.
- Calling concentration risk a type of default. Fix: Concentration is about portfolio structure. Each borrower may be sound, yet the bunching makes the portfolio vulnerable to one shock.
- Saying management approves the credit policy. Fix: Write that the board approves the policy; management implements it through procedures.
- Letting the business team rate and sanction its own loans. Fix: Stress separation of the credit risk function from the business lines and the use of committee approval for larger loans.
- Treating internal and external ratings as the same thing Fix: State who assigns it: the bank (internal, for its own decisions, pricing and IRB capital) versus a SEBI-registered agency (external, public, used for standardised risk weights).
- Listing the 5 Cs without applying them to the case Fix: Attach a fact and a verdict to each C, then conclude.
- Using the sanctioned limit as EAD instead of drawn amount plus CCF × undrawn. Fix: Always compute EAD = drawn + CCF × undrawn. Use the CCF given in the question.
- Taking LGD as the recovery rate. Fix: Write LGD = 1 − recovery before any multiplication.
- Dividing capital by total assets instead of RWA Fix: CRAR always has RWA in the denominator. Weight every asset first.
- Applying the risk weight to the notional of an off-balance sheet item Fix: Multiply by the CCF first, then by the counterparty risk weight.
Exam tips
- For 'identify the type' MCQs, look for the root cause in the scenario: loan repayment, trade settlement, bunching of exposure, or foreign country conditions.
- In written answers, define first, list sources, then classify. This order earns marks for structure.
- Write the expected loss formula only when numbers are given; otherwise just define the terms PD, LGD and EAD.
- Show a simple percentage calculation for concentration questions and state your conclusion in words.
- Always end with a control or mitigation point to show application, not recall.
- Case questions reward application: always use the amounts, ratings and names given before adding theory.
- In limit problems, show limit, existing exposure, headroom and proposal in four clear lines, then conclude.
- Name the board, the risk committee and the independent credit risk function; examiners look for who does what.