It is now customary to use the notation B.C.E and C.E. in dating systems to distinguish between the era before a certain event and the era after it. The term "Before the Common Era" has replaced "Before Christ" and "Common Era" has replaced "Anno Domini" (after Christ).
This was done in order to pacify those who reject Jesus as Christ, or those who simply would not like His name mentioned. I will not get into a monologue about this, but merely remind the reader that changing the term to common era does not alter the beginning of the calendar.
This brings me to a completely new thought. The calendar that the western world has used these 2,015 years began when Jesus of Nazareth was BORN. What day do we celebrate that? Christmas. What day do we celebrate the new calendar year? New Years Day. Why?
Wouldn't it make sense to celebrate the anniversary of the event that prompted the calendar year to begin on the same day that we celebrate the beginning of the calendar year?
Celebrating Christmas on New Year's Day would be the most logical thing to do.