How to change mouse speed of the login window? I prefer a fast tracking speed for mouse on my MacBook.

　 

However, this setting is only good for the logged in user. When I logged out, the mouse is slow again.

How can I change the mouse tracking speed in the login window (i.e. when all users are logged out)?
If you are saying that you would like to set the mouse tracking speed for all users of the system I do not believe there is a way to do that.  Each will have his/her own preference.

If you are saying that when you set your preference and then log out/log in under the same user and unexpectedly find that your preferences are not retained then there should be a fix.

Likely cause ,either:

The the permissions on the preference file are set incorrectly --  This might be fixed in disk utility -- repair permissions. Logout and then login.

or

The permission file is corrupt.  You should move it to the desktop, logout, login and set the permissions. Should stick now.  I believe the preference is stored here:
~/Library/Preferences/com.apple.driver.AppleHIDMouse.plist