For the purposes of this formula,(1) A is the lesser of(a) an amount equal to the total (in this section referred to as “the total tax charged in respect of the immovable”) of the tax that was or would, but for sections 75.1 and 80, have been payable by the registrant in respect of the last acquisition of the immovable by the registrant and the tax that was payable by the registrant in respect of improvements to the immovable acquired or brought into Québec by the registrant after the immovable was last so acquired, and
(b) an amount equal to the tax calculated on the fair market value of the immovable at the particular time;
(2) B is the extent, expressed as a percentage of the total use of the immovable by the registrant at the particular time, to which the registrant reduced the use of the immovable in commercial activities of the registrant at the particular time; and
(3) C is(a) where the registrant was entitled to claim a rebate under sections 383 to 397 in respect of any tax included in the total tax charged in respect of the immovable, or would have been so entitled but for the fact that the registrant last acquired the immovable for use exclusively in commercial activities of the registrant, the difference between 100 % and the percentage prescribed for the purposes of section 386 or 386.1 that applied, or would have applied, in determining the amount of that rebate, and
(b) in any other case, 100 %.