User blog:Opheuchus/Why the new decade starts after 2020

Hello. A survey went online and according to it, 64% of people think that the new decade starts in 2020. I for one know that this is wrong, so I'm going to re-establish every definition of every term that matters to this problem

Decade
A decade is a span of 10 years, which makes this seem so simple.

Calendar Decade
However, let's look at it this way. A calendar month is April, but April 20th-May 20th isn't a calendar month even though it's technically a month. It simply does not fit into our modern-day calendar. It just doesn't work. It just doesn't!

Cardinal Decade
A cardinal decade groups years based on their tens digit. The singles are 1-9, the sixties are 1960-1969, and the twenties are 2020-2029. And here's the tiny detail that most people misinterpret. These are not calendar decades. They do not fit in the calendar in any way. If 2020-2029 is a calendar decade, then 0-9 must be a calendar decade as well. However, since there is no "Year 0", such a system is impossible.

Astronomy's Side
However, not all calendars agree with the one that's used internationally. The Astronomer's calendar does include a Year 0. You might think that this is a good argument to take into this debate, but the astronomers explicitly state that 2021 is the start of a new decade.

The Catchiness of Decades
Now, it just seems to make sense to group years into decades based on their relatability, and grouping 2021 with 2030 just doesn't seem right. However, it is right. It's just counterintuitive.