subclause (I) shall be 20 percent, 30 percent, 40 percent, 50 percent, 60 percent, 70 percent, or 80 percent of area median gross income. . (b) Rules relating to next available unit Subparagraph (D) of section 42(g)(2) of the Internal Revenue Code of 1986 is amended— (1) in clause (i), by striking clause (ii) and inserting clauses (ii), (iii), and (iv) , (2) in clause (ii)— (A) by striking If and inserting In the case of a project with respect to which the taxpayer elects the requirements of subparagraph (A) or (B) of paragraph (1), if , (B) by striking the second sentence, and (C) by striking Next available unit must be rented to low-income tenant if income rises above 140 percent of income limit in the heading and inserting Rental of next available unit in case of 20–50 or 40–60 test , and (3) by adding at the end the following new clauses: (iii) Rental of next available unit in case of average income test In the case of a project with respect to which the taxpayer elects the requirements of subparagraph (C) of paragraph (1), if the income of the occupants of the unit increases above 140 percent of the greater of— (I) 60 percent of area median gross income, or (II) the imputed income limitation designated with respect to the unit under paragraph (1)(C)(ii)(I), clause (i) shall cease to apply to any such unit if any residential rental unit in the building (of a size comparable to, or smaller than, such unit) is occupied by a new resident whose income exceeds the limitation described in clause (v). (iv) Deep rent skewed projects In the case of a project described in section 142(d)(4)(B), clause (ii) or (iii), whichever is applicable, shall be applied by substituting 170 percent for 140 percent , and— (I) in the case of clause (ii), by substituting any low-income unit in the building is occupied by a new resident whose income exceeds 40 percent of area median gross income for any residential rental unit and all that follows in such clause, and (II) in the case of clause (iii), by substituting any low-income unit