difficult development areas (a) In general Subclause (II) of section 42(d)(5)(B)(iii) of the Internal Revenue Code of 1986 is amended by striking 20 percent and inserting 30 percent . (b) Effective date The amendment made by this section shall apply to designations made under section 42(d)(5)(B)(iii) of the Internal Revenue Code of 1986 after December 31, 2017. IV Reforms relating to Native American assistance 401. Selection criteria under qualified allocation plans (a) In general Subparagraph (C) of section 42(m)(1) of the Internal Revenue Code of 1986 is amended by striking and at the end of clause (ix), by striking the period at the end of clause (x) and inserting , and , and by adding at the end the following new clause: (xi) the affordable housing needs of individuals in the State who are members of Indian tribes (as defined in section 45A(c)(6)). . (b) Effective date The amendments made by this section shall apply to allocations of credits under section 42 of the Internal Revenue Code of 1986 made after December 31, 2017. 402. Inclusion of Indian areas as difficult development areas for purposes of certain buildings (a) In general Subclause (I) of section 42(d)(5)(B)(iii) of the Internal Revenue Code of 1986 is amended by inserting before the period the following: , and any Indian area . (b) Indian area Clause (iii) of section 42(d)(5)(B) of the Internal Revenue Code of 1986 is amended by redesignating subclause (II) as subclause (III) and by inserting after subclause (I) the following new subclause: (II) Indian area For purposes of subclause (I), the term Indian area means any Indian area (as defined in section 4(11) of the Native American Housing Assistance and Self Determination Act of 1996 ( 25 U.S.C. 4103(11) ). . (c) Eligible buildings Clause (iii) of section 42(d)(5)(B) of the Internal Revenue Code of 1986, as amended by subsection (b), is amended by adding at the end the following new subclause: (IV) Special rule for buildings in Indian areas In the case of an area which is a difficult development