; and (3) by inserting after clause (viii) the following new clause: (ix) attributable to withdrawal of interest or other income earned on excess contributions (as defined in section 4973(b) (without regard to the second to last sentence thereof)) to an individual retirement plan. . (b) Effective date The amendments made by this section shall apply to any determination of, or affecting, liability for taxes, interest, or penalties which is made on or after the date of the enactment of this Act, without regard to whether the act (or failure to act) upon which the determination is based occurred before such date of enactment. Notwithstanding the preceding sentence, nothing in the amendments made by this section shall be construed to create an inference with respect to the law in effect prior to the effective date of such amendments. IV Defined benefit plan reforms 401. Cash balance (a) In general Section 414, as amended by this Act, is further amended by adding at the end the following new subsection: (bb) Projected interest crediting rate For purposes of this part, in the case of an applicable defined benefit plan which provides variable interest crediting rates, the interest crediting rate which is treated as in effect and as the projected interest crediting rate shall be a reasonable projection of such variable interest crediting rate, not to exceed 6 percent. . (b) Amendment of Employee Retirement Income Security Act of 1974 Section 210 of the Employee Retirement Income Security Act of 1974 ( 29 U.S.C. 1060 ) is amended by adding at the end the following new subsection: (g) Projected interest crediting rate For purposes of this title, in the case of an applicable defined benefit plan (within the meaning of section 203(f)(3)) which provides variable interest crediting rates, the interest crediting rate which is treated as in effect and as the projected interest crediting rate shall be a reasonable projection of such variable interest crediting rate, not to exceed 6 percent. . (c) Effective date The amendments