iPhone's calculated (iCloud) backup size doesn't make sense
I'm having some issues with iCloud backup and my iPhone 5. It has been backing up dutifully for a good while now ever since I deleted a large portion of photos from my camera roll to reduce the size of the phone's backup so I'd have enough room in iCloud's paltry—and at this point embarassing—5 GB limit. In the iCloud backup settings now, though, it is calculating the backup to be 5.5 GB, which just doesn't make sense from the app breakdown it's showing me. I deleted the backup and turned iCloud backup off for a few hours, thinking it might've just been a glitch, but it's still showing a backup size of 5.5 GB. Has anyone else had this issue where the backup size just doesn't comport with the breakdown that it shows?
iPhone 5, iOS 7.0.4