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WikiProject Time assessment rating comment[edit]

Want to help write or improve articles about Time? Join WikiProject Time or visit the Time Portal for a list of articles that need improving. -- Yamara 11:48, 11 January 2008 (UTC)


0 to 9 or 1 to 0?[edit]

"In that sense, the first decade of the 20th century indicates a period from January 1, 1900 until December 31, 1909."

But the 20th century began in 1901. So surely the first decade of the 20th century is 1901 to 1910.

To put it differently, it's the 191st decade. Now we're in the 201st decade, which goes from 2001 to 2010. Of course, this means that pluralised multiples of 10 aren't calendar decades ... though I suppose you could call the 1990s the 199.9th decade.... -- Smjg 00:43, 15 November 2006 (UTC)

Well I think that a Decade like the ‘Nineties’ is from 1990 to 1999, and do not think that 1990 is still in the 1980s! Websters Twentieth Century Dictionary says of the thirties: the years from thirty through thirtynine (of a century or a person’s age). Similarly the Concise Oxford Dictionary: fifty (in pl) numbers etc, esp years of a century or life, from 50 to 59

PS: they both define Decade as ten years, or a group of ten (see below re the Netherlands, ie decade is not used for ten days in English) Hugo999 (talk) 13:22, 6 May 2008 (UTC)

Wikipedia has uncountable numbers of conflicts and errors. Wikipedia does get the page about centuries right:

"According to the Gregorian calendar, the 1st century AD started on January 1, 1 and ended on December 31, 100. The 2nd century started at year 101, the third at 201, etc. The n-th century started/will start on the year 100×n - 99. A century will only include one year, the centennial year, that starts with the century's number (e.g. 1900 is the final year in the 19th century)."

If a century starts with the year 1 then the first and subsequent decades in a century must start with 1. —Preceding unsigned comment added by (talk) 20:46, 31 May 2009 (UTC)

You're taking it as a given that language is always consistent. • Either way, reasoning this out is original thought. We need to find sources. —DragonHawk (talk|hist) 22:36, 31 May 2009 (UTC)

Good sources are on the NASA site and the US Navy Oceanography site. They say: Years of the Gregorian calendar, which is currently in use today, are counted from AD 1. Thus, the 1st century comprised the years AD 1 through AD 100. The second century began with AD 101 and continued through AD 200. By extrapolation we find that the 20th century comprises the years AD 1901-2000. Therefore, the 21st century began with 1 January 2001 and will continue through 31 December 2100.

How simple can it get. If the century and millennium start wit the year 1 so does the decade. —Preceding unsigned comment added by (talk) 01:56, 1 November 2009 (UTC)

Your "if the century and millennium start wit the year 1 so does the decade" is patently original thought. You need to cite sources that specifically talk about decades. — Moreover, there is a crucial difference that you neglect: millennia and centuries are typically labeled with ordinal numbers (21st century), while decades are named with prefixes (nineteen-sixties = those years that are of the form nineteen-sixty-something = 1960–1969.) Your argument would have some validity only if decades were indeed numbered ordinally ("197th decade"). That, however, is not done, so your argument is baseless. --Jmk (talk) 09:34, 16 November 2009 (UTC)
Additionally, the article is currently making statements that are out of place in an encyclopedia attempting to follow facts. It's saying things like "appropriately numbered," "proper definitions, "many people throughout the world mistake a decade," "common use for this may be for ease of grouping," "technically," "correct usage" and "should be," that are all statements biased in a normative fashion or that come through as original research. The final "although both are in common usage" also seems false considering that 0-9 is by far the more common way to group decades nowadays, as far as making lists or marking events is concerned, at least in regard to the western world and the Gregorian calendar. It's pretty established that a week starts with Sunday, for example. Most almanacs put it first and it's common parlance to say it's first. There's no such "official" way to define a decade, and the more common usage is the 0-9 use, including even special celebrations for dates like the year 2000, which are generally taken divide centuries or millenniums.
Let's also keep in mind the calendar was made retrospectively. People didn't start using it right after Christ was supposedly born but 500 to 750 years after that, and the bulk of uses have more to do with relatively recent dates rather than those of the ancient world, so it's usually not a problem if the "first decade" were to appear incomplete when dividing years in the 0-9 fashion. Who is like God? (talk) 03:33, 15 December 2009 (UTC)
Section removed, as being mostly absurd. Thanks for pointing it out. — Arthur Rubin (talk) 08:10, 15 December 2009 (UTC)
According to ISO 8601 the Week starts on Monday, and there is a year 0. —Preceding unsigned comment added by (talk) 04:07, 24 December 2009 (UTC)
0 to 9 is completely false. We start by counting with 1 and end with 10. Furthermore, there is no year zero in the calendar. The first decade AD began with the year 1, and therefore every consecutive decade, century and millennium all began and will forever begin with a year 1. Very simple. — (talk) 11:20, 19 December 2009 (UTC)
And by the way: This is not original research, because according to ISO 8601:2004 the non-existent "year zero" equals the calendrical year 1 BC. See Year zero. Stop filling Wikipedia with nonsense. — (talk) 11:25, 19 December 2009 (UTC)
See also Off-by-one_error#Fencepost_error. — (talk) 11:46, 19 December 2009 (UTC)
Sorry, but ISO 8601:2004 says nothing about decades. It does not even contain the word "decade". So the standard gives absolutely no support for the "1961–1970" idea; that idea is still original research. — Interestingly, the standard does contain the word "century": on page 13, we learn that the two-digit notation "19" indicates a century, where six digits have been omitted from the date string. In other words, "19" refers to the period from 1900-01-01 to 1999-12-31, since those are the days that give "19" if you omit the last six digits. --Jmk (talk) 06:48, 20 December 2009 (UTC)

I have two issues with the current wording: First, it says "usually" 1-10 and "commonly" 0-9. These statements seem to be at odds, since "usually" and "commonly" have similar meanings in context. The only citations I have found online so far about common and accepted usage would be, and it indicates no starting date requirement for a decade. (A bit of original thought here: I expect the issue is because of the proximity to the "3rd millennium" debate and the lack of a common term indicating the 2000-2009 interval as one would've had in 1990-1999 in '90s.) Second, I do not see any reputable and widely accepted sources that demand that a decade be counted from any reference point. In fact, decade has a broader meaning than even "10 year interval". See Decade Counter for example. Also, interesting point (and though not an authoritative source) Janet Jackson's album Design of a Decade indicates the 10 year period of 1986-1996. Final point: Wikipedia itself identifies decades in the xxx0-xxx9 interval in List of decades. —Preceding unsigned comment added by (talk) 20:12, 19 December 2009 (UTC)

I'd suggest that this whole debate is a straw man argument on both sides. The only consensus definitions for the word decade refer to the interval, not the starting point. (See citation above.) Each faction is presuming references to "the decade" refer to the interval with their preferred starting point, and then concludes the other faction is false for being inconsistent with this tacked-on presumption. As such, I propose the page be revised to include a section indicating "controversy" and that each side of the argument be elaborated upon in its own section without criticism of the other. The main definition should then refer to only the part for which there is consensus: the definition of an interval of 10 years, without regard to a starting point. —Preceding unsigned comment added by (talk) 02:42, 20 December 2009 (UTC)
I don't think your observation of "straw-men on both sides" is correct. The only folks who cling to "the" decade seem to be the ones who want to use ordinal numbers (first decade, second decade, ..., perhaps then 197th decade?). Their claim that the common "initial digits" definition is somehow "wrong" is based on this assumption of there being "the" decade. — If the common ground is that any consecutive ten years is a decade (I'm fine with that, and it is supported by dictionaries), then obviously e.g. 1960—1969 is a decade and there's nothing wrong with that. We can then proceed to explain how this decade is called (nineteen-sixties), again supported by references. Any claims or insinuations that this common system is somehow "incorrect" are out of place in the article. I have now revised the article accordingly. --Jmk (talk) 04:12, 20 December 2009 (UTC)
There's a subtle shift in language there. No one should contest that 1960-1969 is a decade. The issue that seems to be in contention is what is being referred to when someone refers to the decade, without further qualification. Your revision skirts the issue by adding qualifiers as in "the decade from 1960 to 1969" followed by a definition of the term "1960s" rather than "the decade" (without qualification). I propose this revision to enhance neutrality (proposing here, rather than editing directly, since I do not want to perpetuate an edit war): "Although any period of ten years is a decade, a convenient and frequently referenced interval is based on the tens digit of the calendar year, as in using 1960s to represent the decade from 1960 to 1969. Often, for brevity, only the tens part is mentioned ('60s or sixties), although this may leave it uncertain which century is meant. These references are frequently used to encapsulate pop culture phenomena that dominated such a decade. In contrast, some writers like to point out that since the common calendar starts from the year 1, its first full decade contained the years from 1 to 10, the second decade from 11 to 20, and so on. The interval from 2001 to 2010 would thus be the 201st decade. However, contrary to practices in referencing centuries, ordinal references to decades are uncommon. Thus, though unqualified references to "the" decade strictly have at least two interpretations, one is forced to consider whether the context is a common cultural reference, a lesser-common ordinal reference, or some other context. An example of the latter is the statement, "during his last decade, Mozart explored chromatic harmony to a degree rare at the time," which merely refers to the last 10 years of Mozart's life without regard to which calendar years are encompassed." —Preceding unsigned comment added by (talk) 23:13, 20 December 2009 (UTC)
I like your further revision. In particular, you managed to describe the tens-digits system much more succintly than I did. --Jmk (talk) 08:04, 21 December 2009 (UTC)

The description on this page "Since there is no year zero (0) in either the proleptic Gregorian calendar or Julian calendar, the decades 0s (both BC & AD) comprised of 9 years instead of 10 and similarly the centuries 0s BC & 0s AD comprised of 99 years." seems patently at odds with the description on the century page ( "According to the Gregorian calendar, the 1st century AD/CE started on January 1, 1 and ended on December 31, 100" Furthermore, the reference to (3) supports the notion that "the" (rather than "a") decades start with 1 and end at 0 -- further down the page in the extended definition section it states: "A decade may also be a well-defined historical period of ten years in a dating system. In that sense, the first decade of the 20th century indicates a period from January 1, 1901 until December 31, 1910." Though...that section sources this wiki... —Preceding unsigned comment added by (talk) 19:23, 28 December 2010 (UTC)

Evidently, they really threw a wrench in things when they did not use a year zero. Practically, I think most people would say that anything that took place in 1960 took place in the 1960s. So that would put the decade from January 1, 1960, to December 31, 1969. On this reasoning, it seems that the first centuries CE and BCE get short changed, each by one year. How does one missing year (year 0) equal two? It really isn't missing, you see, because the question really amounts to a counting discrepancy that gets pushed outward toward both ends of the number line -- befuddling plenty of people even tens of centuries. (talk) 11:55, 19 August 2011 (UTC)

10 days or 10 years?[edit]

In the Netherlands, a decade means 10 days, and a decennium means 10 years. The Dutch Wikipage says that a decade meaning 10 years, is in fact wrong. What is the true meaning of ab decade, and who is right? --Robster1983 16:17, 12 June 2007 (UTC)

I'm not sure I understand what you mean by "true meaning" when talking about words in different languages. In Norwegian, hat means hatred but in Hungarian, hat is the numeral 6 (wikt:hat). Which one is the true meaning? Perhaps they are both wrong and the true meaning of hat is a covering for the head? If you want to find out what the Dutch word decade means, I guess a Dutch dictionary would be the place to start, not the English Wikipedia. --Jmk (talk) 06:26, 20 December 2009 (UTC)

I agree with Jmk however would like to add the following comment: in French (or in German) a décade means ten days, however may also mean ten years (from English influence). In order to avoid this ambiguity, "décade" has been progressively replaced with "décennie" to describe a ten years period. It seems that there is no equivalent in English to describe a ten days period (?). Yanndudo (talk) 09:48, 6 January 2010 (UTC)

English has the term "fortnight" to cover a 14 day (or night) period, but yeah, no 10 day period. There doesn't need to be a one for one with each language. fcsuper (How's That?, That's How!) (Exclusionistic Immediatist ) 02:50, 3 March 2010 (UTC)


decade means that somebody is lower in something than somebody else —Preceding unsigned comment added by (talk) 23:29, 31 January 2008 (UTC) That would be decayed, not decade, buddy. Time for some spelling practice! —Preceding unsigned comment added by (talk) 05:57, 2 January 2011 (UTC)


Editors (or perhaps one editor) under different IPs keep confusing the article and pushing [1] [2] the idea that an ordinal reference would be the "proper" way of counting decades, and that e.g. the 1960s would include the year 1970 (definite nonsense), apparently against the consensus reached on this talk page. They do not seem to be interested in joining the discussion here, however. It might be deliberate vandalism, or perhaps simple neglect of common editing practices. Either way, perhaps this article should be semi-protected, to encourage those editors to raise their issues on the talk page instead of edit-warring. --Jmk (talk) 20:54, 1 January 2010 (UTC)

And what's this idea about the 197th decade? Original thought or not, it's a simple fact that nobody who speaks English refers to ANYTHING as "the 197th decade" regardless of when it begins or ends, regardless of whether the subject is informal writing, or the writing of science or history. This is fluff that assumes that "decades" are "wrong" if they include years that end in 0 as the last year of a decade rather than the first. This assumes that somehow, almost everyone who speaks English is doing it "wrong". Utter prescriptivist nonsense, and out of place for Wikipedia. (talk) 03:40, 25 August 2011 (UTC)

"two thousands" ?[edit]

'For example, the decade commonly referred to as the "two thousands" ended on December 31, 2009.'

Who calls it this? All I ever see used is "the noughties". Graspee (talk) 08:40, 4 January 2010 (UTC)

I don't see it commonly referred to as anything in particular. — Arthur Rubin (talk) 01:03, 7 January 2010 (UTC)
I removed the sentence. It doesn't seem to add anything. — Arthur Rubin (talk) 01:23, 7 January 2010 (UTC)

From what I understand, the first decade of 20th Century also had no nickname during that 10 year period. The Aughts was not really adopted until after the decade was over. We are kinda in the same situation now. Who knows what will take hold this time around, as people seem afraid of less common words these days. fcsuper (How's That?, That's How!) (Exclusionistic Immediatist ) 02:54, 3 March 2010 (UTC)


The lead paragraph includes:

This etymology is sometime confused with the Latin decas (ten) and dies (days), which is not correct.[1]

Problems: 1. The reference is to a French dictionary, which is not appropriate for the etymology of an English word. 2. The French dictionary says the word derives from Latin (which in turn derived from Greek). says the English word derives from French, via Latin and Greek. So I am changing the lead paragraph to reflect this.UnvoicedConsonant (talk) 19:24, 29 May 2013 (UTC)

turn of decade?[edit]

Not a native speaker, I was looking here to understand if 1929-1930 were the turn of the twenties or of the thirties... not found. I think this is much more important than the dispute 0-9 or 1-10. If one speaks of decades, he is not up to mathematical precision, so that it does not really matter; otherwise one tells the exact range explicitly. --Esagherardo (talk) 05:31, 6 October 2015 (UTC)