Recovery D drive slighty fragmented

Hi all,
Just a minor issue I wish to get to the bottom of. After a system recovery last October on my Hewlett Packard PC due to some software causing blue screens, I have just discovered after defragging my main C drive, I have noticed that the "D" partition which holds all the necessary recovery info is just 2% defragmented. As nothing is written to this part of the disc I wonder how this has happened, unless it has always been like that. Usually when I do a recovery, I immediately turn off the "auto-schedule defrag" program so I can do it whenever I wish. But this time I didn't and obviously the auto-defrag has scanned that part of the drive at one time and reported a 2% fragmentation. Any ideas on why this could be? If it isn't a problem, I'll leave it as it is. Or would it be worth a quick defrag just to get everything in order? The OS is Windows 7. Thanks in advance.

Good rule of thumb, don't mess with stuff that is not broken.