Mr. John McCarthy:

On the basis of the information it has from its billing system and from the extent to which it has meters in place, it will be able to work through the product subsidy, the child allowance - again, depending on the number of children it has registered on its system as being claimed for - and the information it has in terms of the extent to which there is usage beyond the cap, which in the ordinary course of events it would be able to charge for if the cap was not in place. All those data are used to underpin the invoice.