Beta The co-efficient which measures the degree of correlation between the returns on shares in a particular company and returns on the stock market as a whole. BACT Business Advisory Committee on Telecommunications Common Costs Costs that are incurred in the supply of all or a group of services provided by the firm and cannot be directly attributed to any one service.
Common costs arise from the existence of economies of scope .
An accounting methodology, where assets are valued and depreciated according to their current replacement cost. The value of discounts from the standard tariff BT is offering in a price control year which BT must maintain in accordance with Condition 24C of its licence, or offer equivalent reductions in standard prices. Economies of Scale These are present where the unit cost falls as the level of output rises. Economies of Scope These are present where the unit cost of a service is lower because the firm also provides other services, ie the provision of service B reduces the unit cost of supplying service A. Efficiency gap The difference between BT's efficiency and that of the bestperforming comparable telecoms companies. Markups A method of recovering the common costs of interconnection, where the markup rate on the incremental cost of a network service is equal across all services.