Social Security Contributions and Benefits Act 1992

9E+W+S[F1The Treasury may by regulations] provide that—

(a)for the purpose of determining whether a contribution is payable in respect of any person, or

(b)for determining the amount or rate of any contribution,

he is to be treated as having attained at the beginning of a week, or as not having attained until the end of a week, any age which he attains during the course of that week.