[summonedskul]

No you are wrong - The word 'decade' is not tied to any specific set of 10 years, so you can mark off any set of 10 years and call it a decade: 2000-2009, or 2005-2014, for example. By your logic the year 2000 should be part of the 90's which it wasn't.

[gsich]

I'm not wrong. Read the "specs".

>By your logic the year 2000 should be part of the 90's which it wasn't.

It was according to the gregorian calendar.

[summonedskul]

but you're still wrong - this decade ends at the last moment of 2019..that's the agreed popular opinion - didn't you even read the Wikipedia link?