3. The annual rate of an official pension may, if a qualifying condition is satisfied or the pension is a widow's pension, be increased by the pension authority in respect of any period beginning on or after 21st November 1983 as follows:—
(1) a pension beginning before 22nd November 1982 may be increased by 3.7 per cent of the basic rate as increased by the amount of any increase under section 1 of the 1971 Act or the existing Orders;
(2) a pension beginning on or after 22nd November 1982 and before 21st November 1983 may be increased by 3.7 per cent multiplied by A/B where
(a)A is the number of complete months in the period between the beginning date of the pension and 21st November 1983, and
(b)B is 12.