85. For the purposes of section 27, when the first computation is made after 1 March 1988, the percentage of the income to be maintained in trust must be equal to a percentage of the average balance of the funds held in trust during the months included between the month preceding the date of coming into force of the Act and the end of the year ending on 31 December preceding the computation, the balance being computed on the basis of the average balance of each of those months.
The percentage referred to in the first paragraph must be equal to the percentage of increase in the monthly average of the Consumer Price Index for the months contemplated in the first paragraph, in relation to the monthly average of the Consumer Price Index for the months immediately preceding the coming into force of the Act up to a number of months equal to the number of months contemplated in the first paragraph.