Differential Backup...

Why are my differential backups of the same size as full database backups ?
I am just adding few rows to it daily.
Thanks.:rolleyes:I'm having the same problem - any ideas on why my differential size is almost as big as a full?|||I found out that there was optmization job that was running on that database every night, just before the differential backup.

Then I changed the job to run once a week before I take a full database backup, and since then I did not had this problem.

Thanks.