equivalent to a tax credit (including any payment) shall be treated as a State income tax credit for purposes of this paragraph and any State benefit which is economically equivalent to a State income tax deduction (including any exclusion from gross income) shall be treated as a State income tax deduction for purposes of this paragraph. (20) Special rule for contributions of built-in gain property to specified school voucher organizations (A) In general In the case of any contribution by the taxpayer of built-in gain property to a specified school voucher organization, such contribution shall be treated for purposes of this title as though such property were sold by the taxpayer at its fair market value immediately before such contribution and the amount of such fair market value were contributed by the taxpayer as a cash contribution to the specified school voucher organization. (B) Definitions For purposes of this paragraph— (i) Built-in gain property The term built-in gain property means any property if, immediately before the contribution of such property, the fair market value of such property exceeds the adjusted basis of such property. (ii) Specified school voucher organization The term specified school voucher organization has the meaning given such term in paragraph (19). . (b) Effective date The amendment made by this section shall apply to charitable contributions made in taxable years beginning after the date of the enactment of this Act.