How do i change the date format to YYYY/MM/dd?

Hi,

I would like to change the date format for the system.

I went to settings > Admin > system settings > format > customize for Local English (canada) and change short date format to YYYY/MM/DD but it does not change it for the system. 

Is there another way to do this? 

I know i can do it for my crm under options but i want to change it globally or at least in settings so all users would see the requested format .

Any idea where i can change it? thank you :)