partial tax
(6) Adjustment in partial tax for estate and generation-skipping transfer taxes attributable to partial tax (A) In general The partial tax shall be reduced by an amount which is equal to the pre-death portion of the partial tax multiplied by a fraction— (i) the numerator of which is that portion of the tax imposed by chapter 11 or 13, as the case may be, which is attributable (on a proportionate basis) to amounts included in the accumulation distribution, and (ii) the denominator of which is the amount of the accumulation distribution which is subject to the tax imposed by chapter 11 or 13, as the case may be. (B) Partial tax determined without regard to this paragraph For purposes of this paragraph, the term “partial tax” means the partial tax imposed by subsection (a)(2) determined under this subsection without regard to this paragraph. (C) Pre-death portion For purposes of this paragraph, the pre-death portion of the partial tax shall be an amount which bears the same ratio to the partial tax as the portion of the accumulation distribution which is attributable to the period before the date of the death of the decedent or the date of the generation-skipping transfer bears to the total accumulation distribution.