Count Column by Group and filter

You're very nearly there. All you need to do is add the condition inside the _countNotTechReview you have in the prior variables.

How many times = 
VAR _maxIndexOf_ProjectAndStage =
    MAXX (
        FILTER (
            'Table',
            'Table'[ProjectId] = EARLIER ( 'Table'[ProjectId] )
                && 'Table'[Stage_Name] = "Tech Review"
        ),
        'Table'[ProjectIndex]
    )
VAR _maxIndexOfProject =
    MAXX (
        FILTER ( 'Table', 'Table'[ProjectId] = EARLIER ( 'Table'[ProjectId] ) ),
        'Table'[ProjectIndex]
    )
VAR _countNotTechReview =
    COUNTROWS (
        FILTER (
            'Table',
            'Table'[ProjectId] = EARLIER ( 'Table'[ProjectId] )
                && 'Table'[ProjectIndex] > EARLIER ( 'Table'[ProjectIndex] )
                && 'Table'[Stage_Name] <> "Tech Review"
        )
    )
RETURN
    IF (
        'Table'[Stage_Name] = "Tech Review",
        _countNotTechReview - ( _maxIndexOfProject - _maxIndexOf_ProjectAndStage - 1 )
    )

AlexisOlson This is the table i get when i try your solution. It is skipping values in the "How many times" column 

Hi Anonymous ,

I made some mistakes in previous post. 

The index([Global index]) should be created of all project. And add one more filter on "_countNotTechReview"

var _countNotTechReview =
COUNTROWS (
    FILTER (
        'NewTable',
        [Global Index] > EARLIER ( 'NewTable'[Global Index] )
            && [Global Index] <= _maxIndexOfProject // one more filter here
            && [Stage_Name] <> "Tech Review"
    )
)

Pbix in the end you can refer.

Best Regards

Community Support Team _ chenwu zhu

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