PUBLIC LAW 100-647—NOV. 10, 1988 102 STAT. 3763 "(II) 'Al' is the contribution rate determined under clause (i) for such employer's first full cal- endar year; "(III) 'A2' is the contribution rate which would have been determined under clause (i) if the employer's second calendar year had been its first full calendar year; "(IV) 'A3* is the contribution rate which would have been determined under clause (i) if the employer's third calendar year had been such employer's first full calendar year; (V) 'B' is the contribution rate for the employer as determined under subparagraph (C) for the employer's second full calendar year; and (VI) *C' is the contribution rate for the employer as determined under subparagraph (C) for the employer's third full calendar year. "(vi) SPECIAL RULE FOR CERTAIN COMPUTATIONS.—For purposes of computing B and C in such formulas— "(I) the percentage rate computed under subparagraph (C), shall not be reduced under clause (viii) of that subparagraph; and "(II) any computations which under subpara- graph (C) are to be made on the basis of a 4-quarter or 12-quarter period ending on a given June 30 shall be made on the basis of a period commencing with the first day of the first calendar quarter that begins after the date on which the employer first commenced paying compensation subject to this Act and ending on that June 30, and the amount so computed shall be increased to an amount that bears the same ratio to the amount so computed as 4 or 12, as appropriate, bears to the number of calendar quarters in the period on which the com- putation was based. "(2) BENEFIT RATIO.—An employer's benefit ratio as of any given June 30 shall be determined by dividing all benefits charged to the employer under paragraph (15) during the 12 calendar quarters ending on such June 30 by the employer's 3-year compensation base as of such June 30 as computed under paragraph (3). "(3) 3-YEAR COMPENSATION BASE.—An employer's 3-year com- pensation base as of any given June 30 is the aggregate com- pensation with respect to which contributions were paid by the employer under this subsection in the 12 calendar quarters ending on such June 30. "(4) RESERVE RATIO.—An employer's reserve ratio as of an^y given June 30 shall be computed by dividing the employers reserve balance as of such June 30, as computed under para- graph (6), by that employer's 1-year compensation base as of such June 30, as computed under paragraph (5). The employer's reserve ratio may be either a positive or a negative figure, depending upon whether the employer's reserve balance is a positive or negative figure. "(5) I-YEAR COMPENSATION BASE.—An employer's 1-year com- pensation base as of any given June 30 is the aggregate com- pensation with respect to which contributions were paid by the