"asset" means the asset provided under the transaction; and

"relevant purpose" means the purpose for which the asset is provided under the transaction.

    (2) A credit arrangement which is a private finance transaction shall be excluded from section 49(2), and the initial cost and the cost at any time of the arrangement shall be nil, if - 

(a) the services provided in relation to the asset consist of, or include, maintaining and repairing the asset and doing everything necessary to ensure that the asset can be used for the relevant purpose in safety and comfort and in accordance with any requirements specified by the authority; and

(b) the authority determine, immediately before the date on which they enter into the transaction, that their estimate of amount B does not exceed 80 per cent. of their estimate of amount A.

    (3) For the purposes of paragraph (2), in relation to a private finance transaction - 

"amount A" means the amount which, apart from this regulation, would be the initial cost of the transaction; and

"amount B" is the amount which would be amount A if for each relevant financial year (within the meaning given to that expression in section 48(2)) the authority assumed - 

(a) that the amount of fees falling to be paid under the transaction would be the minimum which could become payable in that year (without there being a breach of any term of the transaction); and

(b) that the minimum extent, rate or intensity of use of the asset for the relevant purpose would be 80 per cent. of the extent, rate or intensity of use estimated by them for that year for the purpose of estimating amount A.

(a) the arrangement is for the carrying out of works consisting of the improvement of the system for heating or lighting a building in which the authority have a freehold or leasehold interest, or the installation of a new system for such heating or lighting; and

(b) the person with whom the arrangement is made is required under the arrangement, or under a separate contract entered into no later than the date of the arrangement, to maintain and repair the system for heating, or, as the case may be, lighting the building concerned.

"I" means the amount which would be the initial cost of the arrangement calculated on the assumptions mentioned in paragraph (2);

"P" means the number of years comprising the period over which the consideration on the part of the authority under the arrangement falls to be given; and

"U" means the number of years which, at the time in question, comprises the unexpired part of that period.

(a) the value of the consideration given by them in respect of the arrangement before or during the financial year in which the arrangement is varied; and

(b) the value of the consideration falling to be given by them in respect of the arrangement, as varied, in any subsequent financial year.

    (2) For each subsequent financial year referred to in paragraph (1)(b), the value of the consideration falling to be given in that year shall be the amount determined by the formula in regulation 14(2), but, for this purpose - 

"x" is the value of the consideration which the authority estimate will fall to be given by them in that financial year in respect of the arrangement as varied;

"r" is the percentage rate of discount prescribed for the financial year in which the arrangement is varied by regulations made by the Secretary of State for the purposes of section 49; and

"n" is the financial year concerned expressed as a year subsequent to the financial year in which the arrangement is varied (so that the first of the subsequent financial years is 1, the next is 2, and so on).