The Telecommunications (Licence Modification)(Standard Schedules) Regulations 1999

62.3  The Licensee shall update the accounting records referred to in paragraph 62.1 no less frequently than monthly and those records shall include in particular the costs (including capital costs), revenue and a reasonable assessment of assets employed in and liabilities attributable to that International Business and, separately, the amount of any material item of revenue, cost, asset or liability which has been either:

(a) charged from or to any other business of the Licensee or Associated Person together with a description of the basis of the value on which the charge was made; or

(b) determined by apportionment or attribution from an activity common to the business and any other business of the Licensee or any Associated Person and, if not otherwise disclosed, the basis of the apportionment or attribution.