2019, each of the dollar amounts in subsections (a) and (b) shall be increased by an amount equal to— (1) such dollar amount, multiplied by (2) the cost-of-living adjustment determined under section 1(f)(3) for the calendar year in which the taxable year begins, determined by substituting 2018 for 2019 in subparagraph (A)(ii) thereof. If any amount after adjustment under the preceding sentence is not a multiple of $50, such amount shall be rounded to the next lowest multiple of $50. . (b) Clerical amendment The table of sections for subpart A of part IV of subchapter A of chapter 1 of the Internal Revenue Code of 1986 is amended by inserting after the item relating to section 25D the following new item: Sec. 25E. Flood insurance expenses. . (c) Effective date The amendments made by this section shall apply to taxable years beginning after December 31, 2018.