(9)The cost of ongoing supervision of a critical benchmark depends on whether it requires ESMA to constitute and chair a college of supervisors for that benchmark, which represents a considerable additional workload. As a result, it is appropriate to differentiate between both cases in establishing supervision fees. By contrast, within the category of critical benchmarks, it should not be necessary to differentiate the supervision fees in accordance with the annual turnover of the administrator, as critical benchmarks by definition have a systemic impact in the Union.