... The calendar we use is based on when the birth of Jesus is believed to have happened. There are years that happened before it, and years that have occurred since. As you clearly are not very intelligent, I will enlighten you. After 1 B.C. came 1 A.D., there was no "Year 0" which fell in between. The first decade A.D was 1 A.D to 10 A.D.
There was, it simply was not called as such. But for the purposes of our current calendar system, it matters.
Yes, a decade is a period of 10 years. But if we're basing them on numbered decades from our existing calendar, then it's 1991-200 and such. If we're simply basing it on the decade as a period of ten years, then why not divide it up starting with 1916-17 through 1925-26? If we're ignoring decade division from 1 A.D, then why not count starting with the inception of the league? That makes more sense than random division.
My point was that it doesn't matter.
Even if you don't have a Year 0, calendars have been adjusted in the past. Who cares if the first decade had only 9 years, or the first millenium only 999? Does that matter any more than the fact some years in different parts of the world subtracted 10-13 days from the year when transitioning from the Julian to the Gregorian calendar? If there was an error in origin, it makes sense to correct it. In this case, it is almost certain that the basis for the AD numbering is incorrect, so what difference does it really make if we just say that a decade or century or millenium 'begins' on the more logical 0 year, if both are factually inaccurate? When Dionysius devised the AD numbering scheme in 525, he calculated that it was 525 years since the incarnation of Christ. Question is, did he mean that the beginning of 525 was 525 years after Christ was born, or that the end of that year would be 525 years. So even if you ignore the fact that his estimation was wrong, we still don't really know if he started at zero or one.
Secondly and more to the point, as I said earlier, when referencing a named decade, it is common practice to include those years with a common tens digit. The 90s = 90-99. Whether or not that is actually the 200th decade of the AD calendar is completely irrelevent.
[edit: decades did start at 0]
Edited by Buppy, 02 December 2010 - 11:52 PM.