03.06.12 0 There was No Year Zero
There was no year zero. The modern Julian calendar ends the B.C. era with December 31, 1 B.C. and the A.D. era begins with January 1, A.D. 1. The time from December 31, 1 BC to January 1 A.D. 1, is one day, not one year. The second century began with the year 101, not 100. This has been problematic for some Bible and history students in calculating the number of years in the B.C. era to the A.D. era. For example, the number of years from January 1, 2 B.C. to December 31, A.D. 4 is 6 years.[1]
[1]. Finegan, Handbook. 134; Metzger, New Testament. 102; See 03.06.02 for additional details.