the case of any taxpayer for any taxable year, the amount allowed as a deduction under this chapter for business interest shall not exceed the sum of— (A) the business interest income of such taxpayer for such taxable year, (B) 30 percent of the adjusted taxable income of such taxpayer for such taxable year, plus (C) the floor plan financing interest of such taxpayer for such taxable year. The amount determined under subparagraph (B) (after any increases in such amount under paragraph (3)(A)(iii)) shall not be less than zero. (2) Exemption for certain small businesses For exemption for certain small businesses, see the amendment made by section 3203 of the Tax Cuts and Jobs Act . (3) Application to partnerships, etc (A) In general In the case of any partnership— (i) this subsection shall be applied at the partnership level and any deduction for business interest shall be taken into account in determining the non-separately stated taxable income or loss of the partnership, (ii) the adjusted taxable income of each partner of such partnership shall be determined without regard to such partner’s distributive share of the non-separately stated taxable income or loss of such partnership, and (iii) the amount determined under paragraph (1)(B) with respect to each partner of such partnership shall be increased by such partner’s distributive share of such partnership’s excess amount. (B) Excess amount The term excess amount means, with respect to any partnership, the excess (if any) of— (i) 30 percent of the adjusted taxable income of the partnership, over (ii) the amount (if any) by which the business interest of the partnership, reduced by floor plan financing interest, exceeds the business interest income of the partnership. (C) Application to S corporations Rules similar to the rules of subparagraphs (A) and (B) shall apply with respect to any S corporation and its shareholders. (4) Business interest For purposes of this subsection, the term business interest means any interest paid or accrued on indebtedness