For the purposes of the formula in the first paragraph,(1) A is the total of(a) all amounts that became collectible and all other amounts collected by the person in the particular reporting period as or on account of tax under section 16, and
(b) all amounts that would be required to be added under section 446 in determining the person’s specified net tax for the particular reporting period if that section were read as if “net tax” were replaced by “specified net tax”; and
(2) B is the total of all amounts each of which is an amount that may be deducted by the person under section 477.16 in determining the person’s specified net tax for the particular reporting period, or that could be so deducted under section 444 or 449 if those sections and section 444.1 were read as if “net tax” were replaced by “specified net tax” and if sections 444.1 and 446.1 were read as if “this chapter” were replaced by “Chapter VIII.1”, and that is claimed by the person in the return filed under this chapter for that period.