ChD 1 March 1991. Concerned with the construction of a rent review clause in lease on a factory in Wales. Complication on additional rent at time of first rent review which was 15% of a capital sum of £60,000. A clause in the lease provided that 15%, (£9,000), was to be increased pro rata with the increase in the basic yearly rent. The basic rental value of the premises as determined on each rent review was to serve as an inflation index for the £9,000 fixed as additional rent. The tenant (G) proposed the hypothetical letting should include the obligation to pay additional rent as it stood at the commencement of the lease which in practice would mean that at the first review date the additional rent would disappear as in Guys & Dolls Ltd v Sade Brothers Catering Ltd . Declared that the additional rent should be disregarded altogether for the purpose of reviewing the basic rent. Plaintiff landlord (B) awarded costs.