4. Top-Down Models in other countries


●U.K.

：

BT has developed a top-down model which, after adjustment with the bottom-up model developed by Oftel (regulator), has been applied to the establishing of interconnection charges in the U.K.


●Germany

：

WIK, a research institute on telecommunication economics, has released a bottom-up model while Deutsche Telekom is developing a top-down model.


●France

：

ART (regulator) will compare an econometric model considering long-term cost efficiency (bottom-up model) with a model based on France Telecom’s accounting (top-down model).


●E U

：

It is stated that the information required to complete a bottom-up calculation of LRIC-based costs should be cross-checked where appropriate by top-down models based on current costs.