“2–(1)The rateable value of a non-domestic hereditament none of which consists of domestic property and none of which is exempt from local non-domestic rating shall be taken to be an amount equal to the rent at which it is estimated the hereditament might reasonably be expected to let from year to year on these three assumptions -(a)the first assumption is that the tenancy begins on the day by reference to which the determination is to be made;(b)the second  assumption is that immediately before the tenancy begins the hereditament is in a state of reasonable repair, but excluding from this assumption any repairs which a reasonable landlord would consider uneconomic;(c)the third assumption is that the tenant undertakes to pay all usual tenant’s rates and taxes and to bear the cost of the repairs and insurance and the other expenses (if any) necessary to maintain the hereditament in a state to command the rent mentioned above.(1A)......(1B).....(2).....(3)Where the rateable value is determined for the purposes of compiling a list the day by reference to which the determination is to be made is—(a)the day on which the list must be compiled, or(b)such day preceding that day as may be specified by the Secretary of State by order in relation to the list.(4)Where the rateable value is determined with a view to making an alteration to a list which has been compiled (whether or not it is still in force) the day by reference to which the determination is to be made is—(a)the day on which the list came into force, or(b)if a day was specified under sub‑paragraph (3)(b) above in relation to the list, the day so specified.(5)Where the rateable value is determined for the purposes of compiling a list by reference to a day specified under sub‑paragraph (3)(b) above, the matters mentioned in sub‑paragraph (7) below shall be taken to be as they are assumed to be on the day on which the list must be compiled.(6)Where the rateable value is determined with a view to making an alteration to a list which has been compiled (whether or not it is still in force) the matters mentioned in sub‑paragraph (7) below shall be taken to be as they are assumed to be on the material day.(6A)For the purposes of sub‑paragraph (6) above the material day shall be such day as is determined in accordance with rules prescribed by regulations made by the Secretary of State.(7)The matters are—(a)matters affecting the physical state or physical enjoyment of the hereditament,(b)the mode or category of occupation of the hereditament,(c)the quantity of minerals or other substances in or extracted from the hereditament,(cc)the quantity of refuse or waste material which is brought onto and per­manently deposited on the hereditament,(d)matters affecting the physical state of the locality in which the heredi­tament is situated or which, though not affecting the physical state of the locality, are nonetheless physically manifest there, and(e)the use or occupation of other premises situated in the locality of the hereditament.(8)The Secretary of State may make regulations providing that, in applying the preceding provisions of this paragraph in relation to a hereditament of a prescribed class, prescribed assumptions (as to the hereditament or other­wise) are to be made.(8A)For the purposes of this paragraph the state of repair of a hereditament at any time relevant for the purposes of a list shall be assumed to be the state of repair in which, under sub-paragraph (1) above, it is assumed to be immediately before the assumed tenancy begins. (9)....(10)If a day is specified under sub‑paragraph (3)(b) above the same speci­fication must be made in relation to all lists to be compiled on the same day.(11)For the purposes of sub‑paragraph (8) above a class may be prescribed by reference to such factors as the Secretary of State sees fit.(12)....(13)....”
ANNEX: Extract from paragraph 2 of Schedule 6 to the Local Government Finance Act 1988 showing the amendments effected by the Act (printed in bold)