Paragraph 17
The number mentioned in paragraph 5 of this Schedule is that produced by dividing by 12 the sum of 10.4 multiplied by the number specified in sub-paragraph (a) of this paragraph and 6.1 multiplied by the number specified in sub-paragraph (b) of this paragraph, namely—
the number of complete months in the period beginning with the date of which the date when the pension begins is the first anniversary and ending with 31st March 1973; and
the number of complete months in the period beginning with 1st April 1973 and ending either with the day preceding that on which the pension begins or with the day preceding the relevant date for the pension, whichever is the earlier;
and for the purposes of sub-paragraph (b) of this paragraph any fraction of a month shall be treated as a complete month.