I did not know that. We just had either the abbreviated date: 28JUN13
The full date: 28 June 2013
Or a standard DTG: 16:55 28JUN13
Most forms were fully online or automated when I retired and the programs would tell you “Incorrect date format” if you input the wrong data. Just look up some online forms. There are still some old forms that use other formats, but most of those are legal or medical forms.
Try going overseas...in South America it’s: mo/dd/yr...I was always confused