Count step stock at specific date

Hi gringo89 ,

We can use the following steps to meet your requirement.

1. add an index column for fact table in Power Query.

2. And we need to create relationships between tables,

3. Then we can create a measure to get the result,

Measure =
COUNTROWS (
    FILTER (
        SUMMARIZE (
            FILTER (
                ALLSELECTED ( 'fact table' ),
                'fact table'[Date event] <= MIN ( 'Dim Date'[Date] )
            ),
            'fact table'[users],
            "LastType",
            VAR maxIndex =
                CALCULATE (
                    MAX ( 'fact table'[Index] )
                )
            RETURN
                CALCULATE (
                    MAX ( 'fact table'[Type event] ),
                        'fact table'[Index] = maxIndex
                )
        ),
        [LastType] IN DISTINCT ( 'Dim Type event'[Type event] )
    )
) +0

BTW, pbix as attached.

Best regards,