2(1)For the purposes of this Schedule—
(a)campaign expenditure incurred by or on behalf of a party registered in the Great Britain register shall (subject to the following provisions of this paragraph) be attributed to each of England, Scotland and Wales in proportion to the number of parliamentary constituencies for the time being situated in that part of Great Britain; and
(b)campaign expenditure incurred by or on behalf of a party registered in the Northern Ireland register shall be attributed solely to Northern Ireland.
(2)Campaign expenditure whose effects are wholly or substantially confined to any particular parts or part of Great Britain—
(a)shall be attributed to those parts in proportion to the number of parliamentary constituencies for the time being situated in those parts, or
(b)shall be attributed solely to that part,
as the case may be.
(3)For the purposes of sub-paragraph (2) the effects of campaign expenditure are wholly or substantially confined to any particular parts or part of Great Britain if they have no significant effects in any other part or parts (so that, for example, expenditure on an advertisement in a newspaper circulating in Wales is to be attributed solely to Wales if the newspaper does not circulate to any significant extent in any other part of Great Britain).
(4)References in this Schedule to campaign expenditure “in” a particular part of the United Kingdom are accordingly to campaign expenditure which is to be attributed to that part in accordance with this paragraph.