in subparagraph (B). (B) Buildings described A building is described in this subparagraph if 20 percent or more of the residential units in such building are rent-restricted (determined as if the imputed income limitation applicable to such units were 30 percent of area median gross income) and are designated by the taxpayer for occupancy by households the aggregate household income of which does not exceed the greater of— (i) 30 percent of area median gross income, or (ii) 100 percent of an amount equal to the Federal poverty line (within the meaning of section 36B(d)(3)). (C) Exception A building shall not be treated as described in subparagraph (B) if such building is a part of a qualified low-income housing project with respect to which the taxpayer elects the requirements of subsection (g)(1)(C). . (2) Conforming amendment Section 42(b)(4)(C) of such Code is amended by striking (h)(7) and inserting (h)(8) . (b) Increase in credit Paragraph (5) of section 42(d) of the Internal Revenue Code of 1986 is amended by adding at the end the following new subparagraph: (C) Increase in credit for buildings designated to serve extremely low-income households (i) In general In the case of any building— (I) which is described in subsection (h)(6)(B), and (II) which is designated by the housing credit agency as requiring the increase in credit under this subparagraph in order for such building to be financially feasible as part of a qualified low-income housing project, subparagraph (B) shall not apply to the portion of such building which is comprised of residential units described in subsection (h)(6)(B) (determined in a manner similar to the unit fraction under subsection (c)(1)(C)), and the eligible basis of such portion of the building shall be 150 percent of such basis determined without regard to this subparagraph. (ii) Allocation rules applicable to projects to which clause (i) applies (I) State housing credit ceiling For any calendar year, no more than 13 percent of the portion of the State housing credit ceiling