Apportionment of net annual value
8. The net annual value specified in Article 5 and determined in accordance with Article 6 shall for each year be apportioned among the districts in accordance with the formula:—
where—
A is the net annual value for that year;
B is the total length of railway track in the district in question, measured in kilometres, which is occupied by the Company and used primarily for the conveyance of railway traffic; and
C is the total length of railway track in Northern Ireland, measured in kilometres, which is occupied by the Company and used primarily for the conveyance of railway traffic.