DD/MM/YY and YY/MM/DD are the only acceptable ones IMO. Throwing a DD in between YY and MM is just weird since days move by faster so they should be at one of the ends and since YY moves the slowest it should be on the other end.
I’m not kidding when I ask: are there really a lot of people using MM/DD/YYYY??
Using a different date format that means the exact same thing anyway does not make you a moron.
I think most Americans do. Or at least it was taught that way in school when I was growing up. Maybe it’s because of the way we speak dates, like “October 23rd” or “May 9th, 2005”.
Regardless, the only true way to write dates is YYYY-MM-DD.
If you use DD/MM/YYYY, dumb sorting algorithms will put all of the 1sts of every month together, all of the 2nds of every month together, etc. That doesn’t seem very useful unless you’re trying to identify monthly trends, which is fundamentally flawed as things like the number of days in the month or which day of the week a date falls on can significantly disrupt those trends.
With MM/DD/YY, the only issue is multiple years being grouped together. Which may be what you want, especially if the dates are indicating cumulative totals. Depending on the data structure, years are often sorted out separately anyways.
YYYY/MM/DD is definitely the best for sorting. However, the year is often the least important piece in data analysis. Because often the dataset is looking at either “this year” or “the last 12 months”. So the user’s eyes need to just ignore the first 5 characters, which is not very efficient.
If you’re using a tool that knows days vs months vs years that can help, but you can run into compatibility issues when trying to move things around.
The ugly truth no one wants to admit on these conversations is that these formats are tools. Some are better suited to certain jobs than others.
The only reason they place month as first is because it is fits how dates are read in English, but that’s not a good reason to keep that format.
I grew up with DD.MM.YYYY. But I think, MM/DD makes sense in everyday usage. You don’t often need to specify dates with year accuracy. “Jane’s prom is on 7th September” – it’s obvious which year is meant. Then it’s sensible to start with the larger unit, MM, instead of DD.
Even in writing you see that the year is always given like an afterthought: “7th September**,** 2023“.
So when you say it out loud you say 7th September, and not September 7th?
I say “The 7th of September” because I was taught British English in school.