Article 35
Assessment of the data quality
1. When assessing whether an institution’s data standards meet the minimum standards for the internal risk-measurement model to be considered reasonably accurate in measuring risks as required by Article 325bi(1), point (f), of Regulation (EU) No 575/2013, competent authorities shall verify whether:
(a) |
the institution documents, as part of its internal policies, any methodology used to fill in time series with missing data points, and whether such documentation contains sound analysis showing that those methodologies do not affect the risk factors’ volatilities and correlations; |
(b) |
the institution has established objective criteria setting out which methodology to fill in time series is used, where more than one methodology is available, and has documented those criteria in its internal policies; |
(c) |
the institution has established, as part of its internal policies, the process to be followed whenever the values in a time series are changed, and whether such process includes the documentation of the performed changes; |
(d) |
the institution does not perform filtering of data, including flooring, capping and exclusions of outliers, unless the institution is able to demonstrate that the excluded data point relates to erroneous or stale data, and the institution documents such an exclusion; |
(e) |
the institution performs periodic quality checks on the time series used for the computation of the expected shortfall risk measure, and documents those checks and the corresponding results are documented; |
(f) |
the institution analyses, as part of the checks referred to in point (e), the effect that missing or replaced data and the methodology used to obtain the time series have on the risk factors’ volatilities and correlations; |
(g) |
the data quality of the time series used by the institution is appropriate. |
For the purposes of point (e), competent authorities shall verify whether the institution monitors, as part of the checks referred to in that point, for each time series:
(a) |
the number of days for which data points were initially missing and were then filled in using a particular methodology; |
(b) |
the number of days for which data points were initially available and have been replaced using a particular methodology; |
(c) |
the number of days with no daily changes; |
(d) |
the maximum number of consecutive days with no daily change. |
2. For the purposes of paragraph 1, point (g), competent authorities shall:
(a) |
require the institution to provide an overview of their time series used in , , , , and , as referred to in Article 325bb of Regulation (EU) No 575/2013, and in the calculation of the stress scenario risk measures, as referred to in Article 7 of Commission Delegated Regulation (EU) 2024/397, and to include in that overview for each time series used:
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(b) |
based on the overview referred to in point (a), identify those times series used for risk factors that may be affected by low data quality; |
(c) |
based on the overview referred to in point (a), select a sample of time series that are characterised by a high number of data points initially missing, and apply the following steps in the following order:
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(d) |
based on the overview referred to in point (b), select a sample of time series characterised by a high number of data points that were initially available but have been substituted by other data points, and apply the following steps in the following order:
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For the purposes of point (b), competent authorities may use, where appropriate, as a basis for the identification referred to in that point, the following indicators:
(a) |
time series with less than 10 % of initially available data points; |
(b) |
time series with 20 consecutive business days without any daily change; |
(c) |
time series with more than 20 % of days with no changes; |
(d) |
time series for which more than 50 % of the initially available data have been changed. |
Competent authorities shall require the institution to justify the use of those time series and, where applicable, the reason why the corresponding risk factor is included in the reduced set of risk factors as referred to in Article 325bc(2), points (a) and (b), and Article 325bc(3), points (a) and (b), of Regulation (EU) No 575/2013.
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, as referred to in Article 325bb of Regulation (EU) No 575/2013, and on the stress scenario risk measures, as referred to in Article 7 of Commission Delegated Regulation (EU) 2024/397.