if such the Secretary determines— (i) the taxpayer has severe liquidity constraints, or (ii) immediate payment would cause undue hardship on an ongoing enterprise. . (2) Rules Not later than 12 months after the date of the enactment of this Act, the Secretary of the Treasury (or the Secretary's delegate) shall establish rules for the application of the amendments made by paragraph (1). (d) Application of accuracy related penalties (1) In general Section 6662(b) of the Internal Revenue Code of 1986 is amended by adding at the end the following new paragraph: (10) Any substantial wealth tax valuation understatement. . (2) Substantial wealth tax understatement Section 6662 of such Code is amended by adding at the end the following new subsection: (m) Application to substantial wealth tax valuation understatement (1) Substantial wealth tax valuation understatement defined (A) In general For purposes of this section, there is a substantial wealth tax valuation understatement if the value of any property claimed on any return of tax imposed by subtitle B–1 is 65 percent or less of the amount determined to be the correct amount of such valuation. (B) Limitation No penalty shall be imposed by reason of subsection (b)(10) unless the portion of the underpayment attributable to substantial wealth tax valuation understatements for the calendar year exceeds $5,000. (2) Increased penalty (A) In general In the case of any portion of an underpayment which is attributable to one or more substantial wealth tax valuation understatement, subsection (a) shall be applied— (i) in the case of a substantial wealth tax valuation understatement which is a gross wealth tax valuation misstatement, by substituting 50 percent for 20 percent , and (ii) in any other case, by substituting 30 percent for 20 percent . (B) Gross wealth tax valuation misstatement For purposes of subparagraph (A), the term gross wealth tax valuation misstatement means a substantial wealth tax valuation understatement, as determined under paragraph (1) by substituting