I’ve been following some of the "end of a decade?" threads going on (Facebook) the last 32 hrs or so, and I’ve done Google and Ask Jeeves searches of my own. I came across ad homs from both sides: 00-09 people tossing out "anal retentive" and "pedantic", 01-10 people throwing out "uneducated" and "unintelligent", but as none of that, whether true or not, has anything to do with the subject in question, I simply made note of it and went on with my search.
I find myself going with the 00-09 decade. The 00-09 people simply made the better argument. As far as I could find, they actually made the attempt to address the history of time, its reckoning and terminology, Year 0, a 01-10 decade, a 00-09 decade, etc, and explain their reasons for their 2009 the end of a decade, which was more than I could find 01-10 decade people doing ("Can’t people count?" is an ad hom not an explanation or reason, and a discussion of the US’s educational system, although a valid topic, still does not address the subject directly).
So Happy New Year and Happy Beginning of a New Decade!
On a side note: although I have come across the "when does the millenium end?" discussion I do not recollect ever coming across the "end of a decade?" discussion before. Someone born on Dec 31, 1969 was born in the 60s, someone born on Jan 1, 1970 was born in the 70s, the 80s didn't include 1990. Decades ran from year ending in a 0 to year ending 9 and when refered to in total used the number next to the last as a descriptive (60s, 70s, 80s, 90s). I don’t remember ever hearing a different view, which of course made me very curious when I did.
When does the new decade start?/Volokh Conspiracy
"So the "turn of the century... See More" was 2000 if you’re talking about the turn from the 1900s to the 2000s, and 2001 if you’re talking about the turn from the 20th century to the 21st century."..."But the decade that we will call the 2010s (or "the tens" or "the teens," whichever the preferred term ends up being) will pretty certainly begin a few days from now, on Jan. 1, 2010, and will run until the end of 2019."
A Little Decadence/Bad Astronomy
"What people were arguing over were things like centuries and millennia, and how there was no year 0, and therefore the last day of the decade is actually December 31, 2010. But that... See More’s not relevant because we don’t measure decades the same way we do centuries."..."If we did reckon decades the same way as centuries then a point would be made that the decade ends in 2010. But we don’t, and in this case there truly is a year 0: the year 2000. So once again, the first decade of the 2000s ends today."
Today is not New Year's Eve or the end of a decade
"Modern experts prefer 7BC, or thereabouts, as Jesus’ birth day – which means that today is actually 18 December 2015.
Is 2009 really the end of a decade?
January 1, 2010