rate The Secretary shall prescribe guidance or regulations for the calculation of the annual percentage rate of interest on a loan for purposes of subparagraph (A)(i), including rules which provide for— (I) the calculation of the annual percentage rate in cases where there is a variable rate of interest, (II) the recalculation of the annual percentage rate where the terms of the loan are modified after the loan is entered into, and (III) the proper taking into account of lump sum payments, orientation and application fees, closing fees, invoice discounting fees, and any other loan fees. (ii) Bank prime rate For purposes of subparagraph (A)(ii), the term bank prime rate means the average predominant prime rate quoted by commercial banks to large businesses, as determined by the Board of Governors of the Federal Reserve System. (4) Special rules for pass-thru entities For purposes of this subsection, if a qualified investment in a qualifying business entity is made by a partnership, trust, S corporation, or other pass-thru entity, the limitations under this subsection with respect to the qualified investment shall apply at the partnership or other entity level and not at the partner or similar level. (c) Qualified investment For purposes of this section— (1) In general The term qualified investment means, with respect to any qualifying business entity, either of the following of the taxpayer: (A) The direct or indirect acquisition of stock, or a capital interest, in the entity at its original issue solely in exchange for cash. (B) A qualifying loan made to the entity. If a taxpayer has or had more than 1 qualified investment in any qualifying business entity for the taxable year or any prior taxable year, all such investments shall be treated as a single qualified investment for purposes of applying this section. (2) Exception for investments made by qualified active investors and related persons Such term shall not include any acquisition or loan made by a taxpayer who, immediately before the acquisition or loan,