“A pension payable under these Rules shall … be increased at each anniversary of the date of its institution by 3 per cent compound. For this purpose the date of its institution shall be regarded as the date on which a pension became payable to the Member under the Scheme or the date of the Member's death if earlier.”
“Provided always that no such alteration or addition shall (1) operate so as to affect in any way prejudicially (a) any pension already being paid in accordance with the Rules of this Deed at the date such alteration or addition takes effect or (b) any rights or interests which shall have accrued to each prospective beneficiary in respect of pension benefits secured under the Scheme up to the date on which such alteration or addition takes effect.”
“The amount of a pension payable under these Rules at each anniversary of the date of its institution of that pension falling on or after1 January 1991 shall… be increased by the lesser of 5% of that amount or such percentage of that amount as represents any increase in the Government's Index of Retail Prices since the immediately preceding anniversary date. For this purpose the date of its institution shall be regarded as the date on which a pension became payable to the Member under the Scheme or the date of the Member's death, if earlier.”