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

"Risk weighted exposure amount at the end of the reporting period" must equal the sum of 8 cells (C08.04.01.01, Bank of England check v09779_m)

A warning on the credit risk and free deliveries: IRB approach to capital requirements: rwea flow statements (CR IRB 4) template (C08.04.01.01), 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

In column "Risk weighted exposure amount" (0010) of Credit risk and free deliveries: IRB approach to capital requirements: rwea flow statements (CR IRB 4) (C08.04.01.01): "Risk weighted exposure amount at the end of the reporting period" (row 0090) must equal the sum of 8 cells (listed below).

What to do if your return fails it

  1. 01Open the table below and find the cells the rule reads.
  2. 02Add up the parts in your return and compare the result with the total.
  3. 03If they differ, a part is missing, a value sits in the wrong cell, or the total is out of date.
  4. 04The Bank of England allows a small rounding difference, worked out from the decimals each value is reported with.
  5. 05It runs only when your filing indicators mark C08.04.01 as reported.
  6. 06This 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: rwea flow statements (CR IRB 4) (C08.04.01.01)

Rows

  • R0010Risk weighted exposure amount at the end of the previous reporting period
  • R0020Asset size (+/-)
  • R0030Asset quality (+/-)
  • R0040Model updates (+/-)
  • R0050Methodology and policy (+/-)
  • R0060Acquisitions and disposals (+/-)
  • R0070Foreign exchange movements (+/-)
  • R0080Other (+/-)
  • R0090Risk weighted exposure amount at the end of the reporting period

Column

  • C0010Risk weighted exposure amount

A worked example

With simple numbers.

Illustrative values
Risk weighted exposure amount at the end of the previous reporting period1,200
Asset size (+/-)800
Asset quality (+/-)450
Model updates (+/-)300
Methodology and policy (+/-)150
Acquisitions and disposals (+/-)100
Foreign exchange movements (+/-)60
Other (+/-)40
Together3,100
What the rule then expects

Risk weighted exposure amount at the end of the reporting period must then be 3,100.

3,100Passes
3,200Fails

A file that reports 3,100 passes. One that reports 3,200 fails, by 100.

The numbers are illustrative, reported to the unit, so the rounding tolerance does not change the result.

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 plain words above spell out the Bank’s formula, with each cell named from its templates. In the Bank of England’s list of validations, word for word:

v09779_m: [C08.04.01.01 (c0010)] {r0090} = {r0010} + {r0020} + {r0030} + {r0040} + {r0050} + {r0060} + {r0070} + {r0080}
Show the formulaShow

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

{t: C08.04.01.01, r: 0090, c: 0010} = {t: C08.04.01.01, r: 0010, c: 0010} + {t: C08.04.01.01, r: 0020, c: 0010} + {t: C08.04.01.01, r: 0030, c: 0010} + {t: C08.04.01.01, r: 0040, c: 0010} + {t: C08.04.01.01, r: 0050, c: 0010} + {t: C08.04.01.01, r: 0060, c: 0010} + {t: C08.04.01.01, r: 0070, c: 0010} + {t: C08.04.01.01, r: 0080, c: 0010}

Every PRA banking rule on C08.04.01.01

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.