The money amount of reduction in the month before the month in which a PIA or an original
rate increases, is increased by the percentage increase applicable to the increased
PIA and rate. To accomplish this, the new PIA (NPIA), or the new unreduced rate (NUR),
is multiplied by the current money amount of reduction (CMAR). The result is then
divided by the current PIA, or the current unreduced rate, to obtain the new money
amount of reduction, thus:
(NPIA or NUR) x CMAR = NMAR
(CPIA or CUR)
The new money amount of reduction is subtracted from the new PIA or the new unreduced
rate to obtain the new monthly benefit amount. This method is applied in all cases
involving single entitlement to actuarially reduced benefits prior to 1/78 as outlined
in the following sections and examples.
However, the following shortcut formula has been substituted in the instructions and
examples throughout this section wherever it would yield equivalent results:
(CMBA x (NPIA or NUR) = NMBA
(CPIA or CUR)