a qualified rural opportunity fund has a reasonable period of time to reinvest the return of capital from investments in qualified rural opportunity zone stock and qualified rural opportunity zone partnership interests, and to reinvest proceeds received from the sale or disposition of qualified rural opportunity zone property, and (C) rules to prevent abuse. (f) Failure of qualified rural opportunity fund to maintain investment standard (1) In general If a qualified rural opportunity fund fails to meet the 90-percent requirement of subsection (d)(1), the qualified rural opportunity fund shall pay a penalty for each month it fails to meet the requirement in an amount equal to the product of— (A) the excess of— (i) the amount equal to 90 percent of its aggregate assets, over (ii) the aggregate amount of qualified rural opportunity zone property held by the fund, multiplied by (B) the underpayment rate established under section 6621(a)(2) for such month. (2) Special rule for partnerships In the case that the qualified rural opportunity fund is a partnership, the penalty imposed by paragraph (1) shall be taken into account proportionately as part of the distributive share of each partner of the partnership. (3) Reasonable cause exception No penalty shall be imposed under this subsection with respect to any failure if it is shown that such failure is due to reasonable cause. . (b) Clerical amendment The table of sections for subchapter Z of chapter 1 is amended by adding at the end the following new item: Sec. 1400Z–3. Special rules for capital gains invested in rural opportunity zones. . (c) Effective date The amendments made by this section shall apply to amounts invested after the date of the enactment of this section. 7. Reporting on qualified opportunity funds and qualified rural opportunity funds (a) In general (1) Filing requirements for funds and investors Subpart A of part III of subchapter A of chapter 61 is amended by inserting after section 6039J the following new sections: 6039K. Returns with respect to