3(1)In the foregoing provisions of this Schedule "the appropriate multiplier " means—
(a)if at the date of the making of the relevant order the house is occupied by the owner thereof and has been owned or occupied by him or by a member of his family continuously during the three years immediately before that date, three times or such other multiple as may be prescribed;
(b)if at the said date the house is not so occupied, one-and-a-half times or such other multiple as may be prescribed.
In this sub-paragraph " prescribed " means prescribed by an order made by the Minister by statutory instrument which shall be of no effect until it is approved by a resolution of each House of Parliament.
(2)In .this Part of this Schedule " rateable value " means in relation to a house the value which, in the valuation list in force at the date on which the relevant order is made, is shown on that date as the rateable value of the house, or, where the net annual value differs from the rateable value, as the net annual value.