Differences between reports LL01 and LS24 for negative stock

Dear friends,

Could you tell me the difference between the reports " Warehouse Activity Monitor" (LL01) and "Stock Per Material" (LS24)..

When the negative stock option is chosen ,LL01 is not displaying certain materials with the negative stock.However these materials with the negative stock are displayed in the report LS24.

What could be the reasons?

Thanks.

Regards,

Krishnan.