Time Duration Calculation

Hi, ramhariessentia 

Please correct me if I wrongly understood your question.

I tried to create a sample by myself based on the information in your screenshot.

The sample pbix file's link is down below.

Total Days Each Project =
VAR currentproject =
MAX ( 'Table'[ProjectID] )
VAR newtable =
SUMMARIZE (
FILTER ( ALL ( 'Table' ), 'Table'[ProjectID] = currentproject ),
'Table'[ProjectID],
"@duration", DATEDIFF ( MIN ( 'Table'[Date] ), MAX ( 'Table'[Date] ), DAY )
)
RETURN
MAXX ( newtable, [@duration] ) + 1

https://www.dropbox.com/s/npv905vo4zi4gsk/ramhariessentia.pbix?dl=0 

Hi, My name is Jihwan Kim.

If this post helps, then please consider accept it as the solution to help other members find it faster, and give a big thumbs up.

Hi,

Thank you for your explanation.

please kindly check the below measure and the link.

I amended the measure to omit    < abc-start ~ next of abc-start >

Total Days Each Project =
VAR currentproject =
MAX ( 'Table'[ProjectID] )
VAR abcactivitystartdate =
CALCULATE (
MAX ( 'Table'[Date] ),
FILTER (
ALL ( 'Table' ),
'Table'[ProjectID] = currentproject
&& 'Table'[Activity] = "abc"
)
)
VAR abcactivityfinishdate =
CALCULATE (
MIN ( 'Table'[Date] ),
FILTER (
ALL ( 'Table' ),
'Table'[ProjectID] = currentproject
&& 'Table'[Date] > abcactivitystartdate
)
)
VAR newtable =
SUMMARIZE (
FILTER ( ALL ( 'Table' ), 'Table'[ProjectID] = currentproject ),
'Table'[ProjectID],
"@duration", DATEDIFF ( MIN ( 'Table'[Date] ), MAX ( 'Table'[Date] ), DAY )
)
RETURN
MAXX ( newtable, [@duration] ) + 1
- DATEDIFF ( abcactivitystartdate, abcactivityfinishdate, DAY )

https://www.dropbox.com/s/npv905vo4zi4gsk/ramhariessentia.pbix?dl=0 

What answer are you expecting in the card visual?  Does this measure work?

Measure 1 = AVERAGEX(VALUES('Sample data'[Project ID]),[Sample Total Project Time])