Capital buffers based on banks’ domestic systemic importance: selected issues

The purpose of this paper is to assist the numerous regulators around the globe who are currently considering ways to impose domestic systemic importance-based capital requirements on banks.

The article discusses in some detail a number of issues from the viewpoint of regulatory practice, mentioning relevant literature where available. Comments partly reflect the experience that the Czech National Bank gathered over the past two years while preparing its own regime of domestic systemic importance-based capital requirements on banks.

The authors stress, among other points, one weakness of the (otherwise well-designed) method suggested by the Basel Committee for Banking Supervision (BCBS) for assessment of banks’ systemic importance: the method is “relative” in that it does not reflect the absolute importance of the banking sector for the economy. The paper also explains that in some cases, use of individual-level rather than consolidated-level data may be preferable, in contrast to what the BCBS guidance suggests. Further, implications of the buffers over a longer term are pointed out.

As far as the authors are aware, this article is the first to comprehensively discuss the main issues surrounding both key steps (systemic importance assessment and determination of buffer level) in the process of introducing buffers based on domestic systemic importance. A number of questions related to these two steps are raised which regulators may appreciate to be reminded of, even if some of the questions are such that it is not possible to give a generally applicable answer to them.