Calculate open tickets and the one with max duration at the moment of given dates

[Madyshq]

I have read some post related to ticket systems, none of them have helped me. I have a common dataset called ITS, with a Key, created_date and resolved_date; if the ticket is unsolved, resolved_date is blank. I calculate the number of open tickets  in a set of dates. For example, every Thursday since the ticket systems started. The dates table would be like this

Thursdays = FILTER('Date',WEEKDAY('Date'[Date])=5 || 'Date'[Date]=TODAY())

 And I calculate the number of open tickets like this:

Open = CALCULATE (

        COUNT ( ITS[Key]),

        FILTER(ALL(ITS),

            ITS[Created] <=[Date]

                && ( ITS[Resolved] > [Date]

                        || ISBLANK ( ITS[Resolved] )

     )  )   )

But I also need to know which ticket had more time opened in every given date, and it's duration. I am an amateur in DAX, have tried some approaches, all of the unsuccessful. 

I hope some of you can help me. Thanks for the time!

[amitchandak]

@Madyshq , refer the blog or attached files can help

https://community.powerbi.com/t5/Community-Blog/HR-Analytics-Active-Employee-Hire-and-Termination-tr...

[Madyshq]

Having your report  as an example. I want to know, in a given list of dates(lets say weekly), which has been the active worker that has worked for longer time, and for how long.

Like:

January 4th- Jonh Doe, 1020 days

January 11th-  Jonh Doe, 1027 days

January 18th- Mary Ann, 980 days (John left the company)

...

Every 7 days till the last date in the dataset- Person- How long have been working

It makes more sense with tickets than workers, but I hope you have an idea. I have the list of the dates , it should be a column in a new table or something, and make the calculations having that column in consideration.

Thank you very much!