of such part IV is amended by striking the item relating to section 21. (c) Effective date The amendments made by this section shall apply to taxable years beginning after December 31, 2017. 3. Enhancement of the Child and Dependent Care Tax Credit (a) In general Section 36C of the Internal Revenue Code of 1986, as redesignated by section 2 of this Act, is amended— (1) in paragraph (1) of subsection (a), by striking 35 percent reduced (but not below 20 percent) and inserting 50 percent reduced (but not below 35 percent)