section or such regulation, the effective date specified by the plan), and (II) ending on the date described in subparagraph (A)(ii) (or, if earlier, the date the plan or contract amendment is adopted), the plan or contract is operated as if such plan or contract amendment were in effect, and (ii) such plan or contract amendment applies retroactively for such period. 109. Additional exemption for housing qualified disaster displaced individuals (a) In general Section 151 of the Internal Revenue Code of 1986 is amended by adding at the end the following new subsection: (f) Additional exemption for certain disaster-Displaced individuals (1) In general In the case of any taxable year beginning in any calendar year beginning after 2011, there shall be allowed an exemption of $500 for each qualified disaster-displaced individual with respect to the taxpayer for the taxable year. (2) Limitations (A) Dollar limitation The exemption under paragraph (1) shall not exceed $2,000, reduced by the amount of the exemption under this subsection for all prior taxable years. (B) Individuals taken into account only once An individual shall not be taken into account under paragraph (1) if such individual was taken into account under this subsection by the taxpayer for any prior taxable year. (C) Identifying information required An individual shall not be taken into account under paragraph (1) for a taxable year unless the taxpayer identification number of such individual is included on the return of the taxpayer for such taxable year. (3) Qualified disaster-displaced individual (A) In general For purposes of this subsection, the term qualified disaster-displaced individual means, with respect to any taxpayer for any taxable year, any qualified individual if such individual is provided housing free of charge by the taxpayer in the principal residence of the taxpayer for a period of 60 consecutive days which ends in such taxable year. Such term shall not include the spouse or any dependent of the taxpayer. (B) Qualified individual