Management Console Audit provides a way to determine who made what changes within Management Console and when.  Audit functionality is always on.

Purging the Audit Report 

Since audit functionality is always on the information will build over time.  Therefore, you can choose to purge the audit information at any time. To purge the audit information press the Delete action.  Then enter the number of days you want to preserve.  The data will be deleted and a record of the purge will be entered into the audit information.