18.—(1) Subject to the provisions of these regulations, retirement compensation to be paid pursuant to regulation 16 to a person who has reached normal retiring age without having elected under either regulation 19 or regulation 20 to take retirement compensation earlier shall consist of—
(a)in the case of a person who has suffered loss of pension rights—
(i)an annual sum equivalent to the loss of any sum which under the last relevant pension scheme would have become payable to him in each year after retiring at normal retiring age;
(ii)a lump sum equivalent to the loss of any lump sum which would have become payable under that scheme on retiring at that age;
assessed in accordance with regulation 17,
(b)in the case of a person who has suffered a diminution of pension rights under the last relevant pension scheme by reason of a diminution of emoluments, the annual sum and the lump sum which respectively bear the same ratio to the sums which would be payable under the preceding provisions of this paragraph, had he suffered a loss of pension rights, as the amount by which his net annual emoluments have diminished bears to his net annual emoluments before diminution, and
(c)in the case of a person who has suffered a diminution of pension rights for any other reason, the sums which would be payable under (a) of this paragraph, had he suffered a loss of pension rights, respectively reduced by the amount of any sum payable under the last relevant pension scheme in each year after retirement compensation becomes payable and by the amount of any lump sum paid or payable under that scheme.
(2) The condition appropriate to the case of a person claiming retirement compensation under this regulation (which in accordance with regulation 17 is to be regarded as having obtained for the purpose of assessing loss or diminution of pension rights) is that the pensionable service which is to be taken into account for the purposes of the last relevant pension scheme is the pensionable service which would have been taken into account if on the date immediately preceding that on which the loss or diminution of pension rights was occasioned—
(a)he had reached normal retiring age and had then retired;
(b)he had complied with any requirement of the last relevant pension scheme as to a minimum period of qualifying service or contribution;
(c)he had continued any additional voluntary contributions until normal retiring age and had completed any payments in respect of added years which he was in the course of making;
(d)he had served for any additional period provided for in regulation 23.
(3) The sum referred to in paragraph (1)(a) which under the last relevant pension scheme would have been payable to a person in each year after retiring at normal retiring age shall be calculated without taking account of any reduction falling to be made in that sum by reason of the provisions of any Act relating to National Insurance, until he reaches the age at which under the last relevant pension scheme that sum would have been so reduced.