(1) The amounts to be allocated to the Strategic Rail Authority for the purposes of sub-paragraph (3) of paragraph 13 of Schedule 26 to the Act, in respect of expenditure by reference to which capital allowances may be made by virtue of sub-paragraph (2) of that paragraph, shall be such amounts as the Secretary of State shall determine to be equal to the amount or amounts which on the assumptions specified in paragraph (2) below would, but for the BTP Transfer, have represented the balance referred to in paragraph (3) below.
(2) The assumptions referred to in paragraph (1) are that—
(a) the activity of the Board comprising the discharge of the functions (including any matters undertaken for the purpose of discharging those functions) transferred by Schedule 18 to the Act had at all times been a separate trade from any other carried on by the Board, and
(b) an accounting period of the Board had ended immediately prior to the time at which the transfer effected by the BTP Transfer comes into effect.
(3) The balance referred to in paragraph (1) above is such a balance as, in calculating the qualifying expenditure of the Board for the purposes of computing the profits of the separate trade referred to in paragraph 2(a) above for the accounting period starting immediately after the accounting period referred to in paragraph 2(b) above, would have constituted the balance referred to in section 25(1)(b) of the Capital Allowances Act 1990 .
(4) Any determination pursuant to paragraph 1 above may be modified by the Secretary of State on one or more occasions if it should appear to him that the total amounts of expenditure attributable to the Board, in relation to any particular category of property by reference to which capital allowances may be made, is different from that taken into account by the Secretary of State when the original determination in respect of the relevant matters, or (as the case may be) any modification previously made under this paragraph to such determination, was made.