For the purposes of this formula,(1) A is the total of the tax that, before the particular time, became or would, but for sections 75.1 and 80, have become payable by the landlord in respect of the last acquisition of the land by the landlord and the tax that was payable by the landlord in respect of improvements to the land that were acquired or brought into Québec by the landlord after the land was last so acquired and that were used, before the particular time, in the course of improving the immovable that includes the land; and
(2) B is the total of the input tax refund and all other rebates that the landlord was entitled to claim in respect of any amount included in the total referred to in subparagraph 1.