14As respects service before 6th January 1964, section 57(1) of this Act shall have effect as if for paragraph (d) thereof there were substituted the following—
“(d)apart from any period before pensionable age, the pension or the said part of it is of an amount not less, when expressed as a weekly rate, than the graduated retirement benefit which would be payable to the person employed in return for an amount of graduated contributions equal to one such contribution paid in each week of the period of service in respect of a weekly payment of remuneration of fifteen pounds.”