That’s one heck of a wise owl.
Yes, I’m aware that some argue that “the decade” doesn’t end until 12/31/2020 since, for instance, “the millennium” didn’t end until 12/31/2000. Depends on what “decade” is being spoken of. The 2010s are certainly over, and no matter how you look at it, it’s clear that 2020 starts the Roaring 20s.
And then, of course, there’s this absolutely definitive word on the subject from XKCD:
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