Given that the number of MPs to be elected and therefore the number of votes to be distributed to the electorate differs from constituency to constituency, it is customary to present the national results on the basis of "theoretical" or "fictitious" electors rather than in terms of the sum of the votes obtained in each constituency.

The number of votes obtained by a party is divided by the number of votes theoretically available to the voter in his or her constituency (for example, the number of votes obtained by each party in the Centre constituency is divided by 21, their score in the South by 23, their score in the East by 7 and their result in the North by 9).

The sum for all the parties and the four constituencies gives a national result in "theoretical" or "fictitious" voters, as if each voter had given his or her (single) vote to a particular party. These 'theoretical' or 'fictitious' voters are used to calculate both the parties' score at national level and the share of nominal votes for each party.