Regarding Splunk Search

[AnujaT]

I have a requirement wherein i have 3 columns, Owning_stream, changeReq Number, Sate_id (proposed, awaiting approval etc). I am able to calculate the maximum of _time group by State_id. But i want to add one more column in the final result which displays the difference between maximum and minimum dates from previous column. 

[richgalloway]

It's not clear to me what you seek, but perhaps this will help.

... | stats max(_time), range(_time) by State_id

The range function calculates the difference between the maximum and minimum values of the given field.