(1) In determining the rates of interest to be used in calculating the present value of future payments by or to an undertaking, regard shall be had to the yields on the existing assets attributed to the life assurance business and, to the extent appropriate, to the yield which it is expected will be obtained on sums to be invested in the future.
(2) For the purposes of paragraph (1), the assumed yield on an asset attributed to the life assurance business, before any adjustment to take account of the effect of taxation, shall not exceed the yield on that asset calculated in accordance with paragraphs (3) to (6), reduced by 7.5 per cent of that yield.
(3) For the purpose of calculating the yield on an asset -
(a) the asset shall be valued in accordance with Part V excluding any provision under which assets may be taken at lower book values for the purposes of any investigation to which Article 5 applies, and
(b) where a particular asset is required to be taken into account only to