State what expected loss (EL) is and compute it.
The idea
Expected loss (EL) is the average credit loss the bank anticipates over the horizon, the mean of the loss distribution. LGD is the loss rate, which is one minus the recovery rate. For one exposure, EL = EAD × PD × LGD. For a portfolio, EL is simply the sum of the individual ELs, because expectations add whatever the correlations. EL is treated as a cost of doing business. It is built into the loan spread and covered by provisions or reserves, and so it does not call for economic capital. A frequent mistake is to use the recovery rate in place of the loss rate, or to multiply by the credit limit instead of the exposure expected at default. EL is not the risk. The variability around it is.
Formulas
Expected loss on one exposure
EL = PD × LGD × EAD
- PD
- the probability of default over the horizon
- LGD
- loss given default, as a share of the exposure
- EAD
- the exposure at default
For a portfolio, add the individual ELs whatever the correlations. Use the loss rate, not the recovery rate.
A practice question
Which expression gives the expected loss on a single credit exposure?
- Exposure at default x probability of default x loss rate. - correct
- Exposure at default x probability of default x recovery rate.Why not: Uses the recovery rate instead of the loss rate.
- Exposure at default x loss rate x (1 - probability of default).Why not: Weights the loss by the probability of survival rather than of default.
- Exposure at default x the square root of probability of default x (1 - probability of default) x loss rate.Why not: Gives the unexpected loss, the standard deviation, not the expected loss.
Expected loss is the mean of the loss: the chance of default times the amount lost given default, EAD x PD x LGD.
A harder one
A bank wants the part of a loan's annual credit spread that just covers expected credit loss. The loan has a one-year PD of 1.5 percent and a loss rate of 45 percent. The expected-loss component of the spread is closest to:
- 150 basis points.Why not: Uses the PD alone and ignores that only part of the exposure is lost.
- 82.5 basis points.Why not: Uses the recovery rate instead of the loss rate.
- 333 basis points.Why not: Divides PD by the loss rate instead of multiplying.
- 67.5 basis points. - correct
EL rate = PD x LGD = 0.015 x 0.45 = 0.00675, or 67.5 basis points of exposure.
The hardest tier
A bank has a USD 12 million credit line, USD 5 million drawn. It expects that 60 percent of the undrawn amount will be drawn before default. The one-year PD is 2.5 percent and the expected recovery rate is 45 percent. The expected loss is closest to:
- USD 126,500. - correct
- USD 68,750.Why not: Uses only the current drawn balance as exposure.
- USD 165,000.Why not: Uses the full limit as exposure.
- USD 103,500.Why not: Uses the recovery rate in place of the loss rate.
EAD = 5 + 0.6 x 7 = 9.2 million; LGD = 1 - 0.45 = 0.55; EL = 9.2m x 0.025 x 0.55 = 126,500.
In the app: 6 practice questions on this outcome, spaced review that brings it back before you forget it.
Start free →More in Capital Structure in Banks
- Judge whether a bank's economic capital is adequate given the credit risk it carries.
- Recognise the three main inputs to economic capital for credit risk, namely loss rate, exposure and the chance of default, and describe each.
- State what unexpected loss (UL) is and compute it.
- Under an assumed binomial distribution, derive the variance of the probability of default.
- Compute UL for a portfolio of credit assets, along with each asset's contribution to it, across differing portfolio mixes, asset features and sizes.
- Explain the derivation of economic capital.
- Account for how the distribution of credit losses is modelled.
- Outline what makes credit risk difficult to quantify.