Transform and summarize data from one table into another...

Hi elietech .

The error was related with the calculation when you have a single day, I already fixed it by changing the formula to:

measure = 
VAR Date_Selection =
    MAX ( 'Dates'[Date] )
VAR Date_Selection_Next = Date_Selection + 1
VAR temp_table =
    FILTER (
        ADDCOLUMNS (
            UpDown;
            "Start";
                DATE ( YEAR ( UpDown[DOWN_START] ); MONTH ( UpDown[DOWN_START] ); DAY ( UpDown[DOWN_START] ) );
            "End";
                DATE ( YEAR ( UpDown[DOWN_STOP] ); MONTH ( UpDown[DOWN_STOP] ); DAY ( UpDown[DOWN_STOP] ) )
        );
        [Start] <= Date_Selection
            && [End] >= Date_Selection
    )
VAR DateStart =
    IF (
        MINX ( temp_table; UpDown[DOWN_START] ) <= Date_Selection;
        Date_Selection;
        MINX ( temp_table; UpDown[DOWN_START] )
    )
VAR DateEnd =
    IF (
        MAXX ( temp_table; UpDown[DOWN_STOP] ) >= Date_Selection_Next;
        Date_Selection_Next;
        MAXX ( temp_table; UpDown[DOWN_STOP] )
    )
VAR Same_day_selection =
    IF (
        MAXX ( temp_table; [Start] ) = MINX ( temp_table; [End] )
            && MINX ( temp_table; UpDown[DOWN_START] ) >= Date_Selection;
        1
    )
RETURN
    IF (
        DateEnd = BLANK ();
        1440;
        IF (
            Same_day_selection = BLANK ();
            DATEDIFF ( Date_Selection; DateStart; MINUTE )
                + DATEDIFF ( DateEnd; Date_Selection_Next; MINUTE );
            1440
                - CALCULATE (
                    SUM ( UpDown[DOWN_DURATION] );
                    FILTER ( temp_table; UpDown[DOWN_START] = DateStart )
                )
        )
    )

Check result below and attach.