The NS90 method is identical to the NS65 method. Refer to RS 00605.040 to determine elapsed years, base years, computation years, divisor months and PIA
            determination. However, if the NH has died prior to 1961, elapsed years go up to the
            year of death even if death is after the year of attainment of retirement age. Although
            elapsed years may equal zero, there must be at least 2 computation years and 24 divisor
            months.
         
         The 1990 amendments permit certain individuals who were not previously eligible for
            a NS65 method to have their benefits calculated by the same formula. New start methods
            prior to the 1965 method are no longer available for new entitlements unless entitlement
            in the month before the month of the new entitlement exists on the record.
         
         NOTE: The primary insurance factor code (PIFC) will be 7 on all NS 90 cases. On existing
            cases where a NS 65 PIA is used the system will use a PIFC of 7 when initial entitlement
            is after 5/92 or when a recomputation applies in 1993 or later. The NS 90 and NS 65
            are identical.