Is 2020 really the start of the new decade?

Parker Milner Contributor
Is 2020 really the start of the new decade?

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Towards the end of 2019, as people were settling into the holiday lull, and reflecting on what had transpired not only over the past year but more broadly over the past 10 years, an interesting debate cropped up on the far reaches of the internet: when does the new decade actually start?

Is it on January 1, 2020, or January 1, 2021? Of course, most people believe that new decades begin with years that end in zero’s. That’s why CNN has dedicated entire series to the ’70s, ’80s, ’90s, and 2000s. But there’s a group of sticklers out there that argue this logic is incorrect. Here’s why:

  • The website Time and Date notes that “contrary to popular belief the 21st century and the third millennium did not begin on January 1, 2000, but one year later, on New Year’s Day 2001.”
  • Mental Floss provides context by saying this is all due to a miscalculation in the 6th century by an abbot named Dionysius Exiguus [who] attempted to calculate the year Jesus was born, but actually missed the mark. Nevertheless, “it became the basis for both the Julian and the Gregorian calendars [and] Dionysius labeled the year of Jesus’s birth with the Roman numeral for one (I). Later on, as St. Bede the Venerable, a monk, was attempting to publish his own version of history, he “recorded the latest year before Jesus’s birth as 1 B.C., leaving no space for a year 0. In fact, the concept of zero didn’t even reach Europe until at least the 12th century.”

The crux of the matter is that based on the abbot and monk’s slightly confusing calculations above, it’s actually only been 2019 years since the year Dionysius determined was 1 A.D. not the round, clean year of 2020. So whose side are you on?

  • If you think 2021 is the start of the new decade you’d actually be in good company. Both the Farmer’s Almanac and the U.S. Naval Observatory have your back.
  • That being said, you may be in the minority at the next cocktail party. Results show that 64% of Americans answered the next decade began on January 1, 2020, and will end on December 31, 2029.

Either way you look at it, one thing’s for sure. You can bet that we’ll be having this same debate in just under ten years from now.