@capnPedro said:
But the European format of 24/12/2007 is best for people. Think about it; the day changes the most, then month, then year. By having the date (which is different most frequently) right at the beginning, you can look at the date and straight away know what day it is. I could guess that it was December 2007 without looking; it's been the same for 24 days already!
So using your logic, a single day changes more than 10's of days so we should write the day as 42. Thus we should write the full date as 42/21/7002.
Since we're used to writing the most significant part of numbers first and we express dates with numbers, the only logical choise is 2007-12-24.