During the representations on our August 2014 draft determinations an error has been identified in the ‘New costs and adjustments’ sheet of the ‘Retail average cost to serve’ model. As a result of this error the economies of scope factor (1.3) has been applied twice to the number of unmetered dual service customers. This resulted in reduced allowed new costs, which has had the knock on effect of reducing the unmetered average cost to serve and the amount of costs that some companies can recover. We have corrected the error and have published the amended retail average cost to serve model. This has increased the unmeasured average cost to serve from £20.73 per customer to £20.77 per customer.