(1) In this section -

'authorised officer' has the same meaning as in section 818;

'proprietary director' has the same meaning as in section 472;

'qualifying employment', in relation to a year of assessment, means an office (including an office of director of a company which would be within the charge to corporation tax if it were resident in the State, and which carries on a trade or profession) or employment which is held -

(a) outside the State in a territory with the Government of which arrangements are for the time being in force by virtue of section 826(1), and

(b) for a continuous period of not less than 13 weeks, but excluding any such office or employment -

(i) the emoluments of which are paid out of the revenue of the State,

(ii) with any board, authority or other similar body established in the State by or under statute;

'the specified amount' in relation to an individual means, as respects the year of assessment concerned, the amount of tax for that year determined by the formula -

where -