be determined by substituting-— (1) such earned income for the preceding taxable year, for (2) such earned income for the taxpayer’s first taxable year beginning in 2020. (b) Earned income (1) In general For purposes of this section, the term earned income has the meaning given such term under section 32(c) of the Internal Revenue Code of 1986. (2) Application to joint returns For purposes of subsection (a), in the case of a joint return, the earned income of the taxpayer for the preceding taxable year shall be the sum of the earned income of each spouse for such preceding taxable year. (c) Special rules (1) Errors treated as mathematical error For purposes of section 6213 of the Internal Revenue Code of 1986, an incorrect use on a return of earned income pursuant to subsection (a) shall be treated as a mathematical or clerical error. (2) No effect on determination of gross income, etc Except as otherwise provided in this subsection, the Internal Revenue Code of 1986 shall be applied without regard to any substitution under subsection (a). (d) Treatment of certain possessions (1) Payments to possessions with mirror code tax systems The Secretary of the Treasury shall pay to each possession of the United States which has a mirror code tax system amounts equal to the loss (if any) to that possession by reason of the application of the provisions of this section (other than this subsection) with respect to section 32 of the Internal Revenue Code of 1986. Such amounts shall be determined by the Secretary of the Treasury based on information provided by the government of the respective possession. (2) Payments to other possessions The Secretary of the Treasury shall pay to each possession of the United States which does not have a mirror code tax system amounts estimated by the Secretary of the Treasury as being equal to the aggregate benefits (if any) that would have been provided to residents of such possession by reason of the provisions of this section (other than this subsection) with respect to section 32 of