entity means— (i) a regulated investment company, (ii) a real estate investment trust, (iii) an S corporation, (iv) a partnership, (v) an estate or trust, and (vi) a common trust fund. (7) Applicable property For purposes of this subsection, the term applicable property means residential rental property or nonresidential real property (as such terms are defined in subsection (e)(2)). . (b) Minimum tax treatment Paragraph (1) of section 56(a) of the Internal Revenue Code of 1986 is amended by adding at the end thereof the following new subparagraph: (E) Use of neutral cost recovery ratio In the case of property to which section 168(n) applies, the deduction allowable under this paragraph with respect to such property for any taxable year (after the taxable year during which the property is placed in service) shall be— (i) the amount so allowable for such taxable year without regard to this subparagraph, multiplied by (ii) the applicable neutral cost recovery ratio for such taxable year (as determined under section 168(n)). This subparagraph shall not apply to any property with respect to which there is an election in effect not to have section 168(n) apply. . (c) Effective date The amendments made by this section shall apply to property placed in service before, on, or after the date of the enactment of this Act, with respect to taxable years ending on or after such date. 4. Elimination of amortization of research and experimental expenditures (a) In general Section 174 of the Internal Revenue Code of 1986 is amended to read as follows: 174. Research and experimental expenditures (a) Treatment as Expenses (1) In general A taxpayer may treat research or experimental expenditures which are paid or incurred by him during the taxable year in connection with his trade or business as expenses which are not chargeable to capital account. The expenditures so treated shall be allowed as a deduction. (2) When method may be adopted (A) Without consent A taxpayer may, without the consent of the Secretary, adopt the method