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2 min readWarningBank of England banking taxonomy 4.1.1Updated 11 November 2026

Number of obligors defaulted during the year should not exceed Number of obligors at the end of the year (OF08.05.00.01, Bank of England check boe_b0354_1)

A warning on the credit risk and free deliveries: IRB approach to capital requirements: back-testing of PD (CR IRB 5) template (OF08.05.00.01), in the own funds (PRA001) return.

Line4 Check runs it on the own funds (PRA001) return, proven on test files, check by check: the same outcome on all three test files of that return.

Check your file for this ruleWhat to do if it fails

The rule in plain words

Number of obligors defaulted during the year should not exceed Number of obligors at the end of the year

In each of 18 rows (listed below) of Credit risk and free deliveries: IRB approach to capital requirements: back-testing of PD (CR IRB 5) (OF08.05.00.01): "Number of obligors at the end of the previous year" (column 0020) must not be less than "Of which: defaulted during the year" (column 0030).

What to do if your return fails it

  1. 01Open the table below and find the cells the rule reads.
  2. 02Compare the values in your return. If the first is smaller than it may be, one of them is wrong: check both before you change either.
  3. 03The Bank of England allows a small rounding difference, worked out from the decimals each value is reported with.
  4. 04It runs only when your filing indicators mark OF08.05.00 as reported.
  5. 05This is a warning. It does not stop the return on its own, but your supervisor may ask you to explain it.

The cells it reads

Credit risk and free deliveries: IRB approach to capital requirements: back-testing of PD (CR IRB 5) (OF08.05.00.01)

Rows

  • R00100.00 to <0.15
  • R00150.00 to <0.05
  • R00250.05 to <0.10
  • R00300.10 to <0.15
  • R00400.15 to <0.25
  • R00500.25 to <0.50
  • R00600.50 to <0.75
  • R00700.75 to <2.5
  • R00800.75 to <1.75
  • R00901.75 to <2.5
  • R01002.5 to <10
  • R01102.5 to <5
  • R01205 to <10
  • R013010 to <100
  • R014010 to <20
  • R015020 to <30
  • R016030 to <100
  • R0170100 (Default)

Columns

  • C0020Number of obligors at the end of the previous year
  • C0030Of which: defaulted during the year

Sheets

  • S0001Total (AIRB approach)
  • S0002Total (FIRB approach and slotting approach)
  • S0006Institutions (FIRB approach)
  • S0009Corporates - Specialised Lending (AIRB approach)
  • S0010Corporates - Specialised Lending (FIRB approach or slotting approach)
  • S0011Corporates - Other general corporates - non-SME (AIRB approach)
  • S0012Corporates - Other general corporates - non-SME (FIRB approach)
  • S0015Retail - Qualifying revolving (AIRB approach)
  • S0016Retail - Other SME (AIRB approach)
  • S0017Retail - Other non-SME (AIRB approach)
  • S0018Retail - Secured by commercial immovable property SME (AIRB approach)
  • S0019Retail - Secured by commercial immovable property non-SME (AIRB approach)
  • S0020Retail - Secured by residential immovable property - SME (AIRB approach)
  • S0021Retail - Secured by residential immovable property non-SME (AIRB approach)
  • S0022Corporates - Financial corporates and large corporates (FIRB approach)
  • S0023Corporates - Other general corporates - SME (AIRB approach)
  • S0024Corporates - Other general corporates - SME (FIRB approach)

Which returns it applies to

Line4 Check runs it on the own funds (PRA001) return on Bank of England banking taxonomy 4.1.1. The Bank of England applies it to own funds (PRA001) returns, as a warning.

The Bank’s own words and formula

The first paragraph of the plain words above is the Bank of England’s own, word for word, from its list of validations. The second spells out its formula, with each cell named from its templates.

Show the formulaShow

The Bank of England's formula. Cells are written as {t: table, r: row, c: column}.

{t: OF08.05.00.01, c: 0020} >= {t: OF08.05.00.01, c: 0030}

Where it applies, in the Bank's words (its scope):

scope({t: OF08.05.00.01, r:0010;0015;0025;0030;0040;0050;0060;0070;0080;0090;0100;0110;0120;0130;0140;0150;0160;0170,z:0001;0002;0006;0009;0010;0011;0012;0015;0016;0017;0018;0019;0020;0021;0022;0023;0024, f: banking, fv: banking_reporting})

Every PRA banking rule on OF08.05.00.01

Checks like this one, run at the point of submission, are the first step to real-time supervision. Line4 builds SupTech software for financial regulators that runs checks like these as each return arrives.