For the purposes of the formula,(1) A is the basic tax content of the immovable at that time;
(2) B is the amount that would be the basic tax content of the immovable at that time if that amount were determined without reference to the total of the amounts used for B in paragraph 2 of the definition of “basic tax content” in section 1; and
(3) C is the tax that is or would be, but for sections 75.1 and 80, payable in respect of the taxable supply.