434R0.9. The net specified supplies of a registrant for a reporting period is the amount determined by the formula
A - B.
In applying the formula provided for in the first paragraph, (1) A is the total of
(a) all consideration for specified supplies made by the registrant that became due, or was paid without having become due, to the registrant in the reporting period, and
(b) all amounts that became collectible, and all other amounts collected, by the registrant in the reporting period as or on account of tax under section 16 of the Act in respect of specified supplies made by the registrant; and
(2) B is the total of all amounts each of which is an amount that the registrant has, in the reporting period, paid or credited to a person as or on account of
(a) a reduction in, or refund of, all or part of the consideration for a specified supply made by the registrant to the person, or
(b) a refund of, or a credit for, tax under section 16 of the Act charged to or collected from the person in respect of a specified supply made by the registrant.