Tardis:Eras

As was agreed through consensus, appendages which establish a year's position relative to year 0 shall be given in terms of "AD" and "BC". This is the overwhelmingly dominant usage within the DWU. BCE and CE may be more "politically correct" because they have no religious overtones, but such designations are very rarely used within the DWU. The Doctor himself has been heard on several occasions to use "BC" and "AD" within televised episodes, making their validity in the DWU hard to refute.

In a separate discussion, it was demonstrated that DWU sources were divided between those that believed in a year 0 and those that didn't. With a year 0, the year 2000 is the start of the second millennium and the 21st century. If there is no year 0, as is generally accepted in the real world scientific community, then 2001 is the the "anniversary date".

Because of the split in DWU fiction, however, we had to choose one or the other. In the end, it was decided to officially "believe in" a year 0, since this made programming of certain templates, like timeline, much easier.