under section 6013. (4) Head of household For purposes of determining the amount of the credit allowed under this section for any taxable year, if a taxpayer filed a return as a head of household for the preceding taxable year, the reduction of the credit allowable to the taxpayer under paragraph (1) shall be determined under paragraph (2) by substituting $60,000 for $30,000 in subparagraph (A) thereof. (5) Inflation adjustments (A) In general In the case of any taxable year after 2019, each of the dollar amounts under paragraphs (1), (2), and (4) shall be increased by an amount equal to— (i) such dollar amount, multiplied by (ii) the cost-of-living adjustment determined under section 1(f)(3) for the calendar year in which the taxable year begins, determined by substituting calendar year 2018 for calendar year 2016 in subparagraph (A)(ii) thereof. (B) Rounding If any increase determined under subparagraph (A) is not a multiple of $50, such increase shall be rounded to the nearest multiple of $50. (b) Definitions For purposes of determining the credit allowed under this section for any taxable year— (1) Eligible individual (A) In general The term eligible individual means an individual— (i) who attained 18 years of age before the close of the preceding taxable year, (ii) whose principal place of abode was in the United States for more than one-half of the preceding taxable year, (iii) who was not a dependent for whom a deduction is allowable under section 151 to another taxpayer for any taxable year beginning in the same calendar year as the preceding taxable year, and (iv) who did not claim the benefits of section 911 for the preceding taxable year. (B) Limitation on eligibility of nonresident aliens The term eligible individual shall not include any individual who is a nonresident alien individual for any portion of the preceding taxable year, unless such individual is treated for such taxable year as a resident of the United States for purposes of this chapter by reason of an election under subsection (g) or