(a) Fiduciary adjustment defined. — The fiduciary adjustment shall be the net amount of the modifications described in § 1106 of this title (including subsection (c) of § 1106 of this title if the estate or trust is a beneficiary of another estate or trust) which relate to items of income or deduction of an estate or trust.
(b) Shares of fiduciary adjustment. — The respective shares of an estate or trust and its beneficiaries (including solely for the purpose of this allocation, nonresident beneficiaries) in the fiduciary adjustment shall be in proportion to their respective shares of the federal distributable net income of the estate or trust. If the estate or trust has no federal distributable net income for the taxable year, the share of each beneficiary in the fiduciary adjustment shall be in proportion to the beneficiary's share of the estate or trust income for such year, under local law or the terms of the governing instrument, which is required to be distributed currently and any other amounts of such income distributed in such taxable year. Any balance of the fiduciary adjustment shall be allocated to the estate or trust.