power.
(4) When withdrawing obligations, the Authority
may, by a reasoned decision, set the final date for
their implementation.
(5) After having conducted a repeated market
analysis, the Authority may amend the imposed
obligations by applying the necessary changes
according to the provisions of this section
concerning the imposition of obligations.
Cost accounting
obligation
51. (1)The Authority shall require operators having
significant market power to establish cost account
ting for the purposes of regulation.
(2) Cost accounting must show separate accounts,
in accordance with international best practices.
(3) Costs relating to regulated and non-regulated
activities are kept separate.
(4) Cost accounting must be by activity-based
costing.
(5) The cost accounting system must be audited
annually by an independent body appointed by the
Authority, the costs of the audit to be borne by the
operator having significant market power which
allow the Authority to publish a cost nomenclature
prior to submission of the reference inter
connection offer for approval.
(6) Pending the implementation of cost accounting,
the interconnection rates shall be calculated on the
basis of the following recommendations
(a) using a regional benchmark;
(b) using an existing cost calculation tool;
(c) using, for an initial period of three years, a
top-down model based on forward-looking
historical costs, before moving to a
model based on a long-run incremental
costs, which gives the
operator with a
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