CA 18 December 1986. Appeal by the VO from a LT decision that the ratepayers` hereditaments situated just outside the Lower Swansea Valley Enterprise Zone were adversely affected by the zone and that this should be taken into account in their valuations under General Rate Act 1967 s20(1)(b) . It was submitted on behalf of the VO that s20(1)(b) was concerned with physical factors or at least with factors which affect the physical use and enjoyment of the hereditament, an interpretation disputed by the ratepayers. CA accepted the VO`s submission in general, but with important guidance as to the implications of their decision. At the material time there were were no physical consequences as a result of the designation of the zone and the LT had erred in taking account the mere designation or existence of the zone. However, the zone might in the future cause the physical changes which could be capable of being taken into account for the purposes of s20(1)(b). If the existence of a zone a