How to cerate a report for time spent while handling a catalog task at different stages.

Hi,

Is there a possibility to generate report for analyzing the time it took for tasks to switch from one state to another.

e.g. time it too from the task was created, amount for time the task was in progress, time it to to complete the task etc.  

Are there any tables which i can use? e.g. task_time_worked.

Kind Regards,

Chetan Tendulkar.