Difference between Database Used and sum of table size

Claude_Delille

Hi,

In NAV 2009 R2, we see a difference between :
- File -> Database -> Information -> Database Used (KB)
- Sum of Size (KB) in Table information

Sometimes the difference is small, sometimes there is a big difference.
For example we have a database where Database Used in Database information is 2.506.400 KB, and the sum of size of all tables is 1.914.232 KB.

Do you know where this difference might come from (we still have a difference after optimization) ?

Thanks

Claude