Time difference between next row

pak

May be a MEASURE instead of a column would handle memory better.

Try this MEASURE

Time Difference Measure =
VAR NextRow =
    CALCULATE (
        MIN ( TableName[Date/Time] ),
        FILTER (
            ALL ( TableName ),
            TableName[Date/Time] > SELECTEDVALUE ( TableName[Date/Time] )
        )
    )
RETURN
    IF (
        SELECTEDVALUE ( TableName[Bit] ) = 1,
        DATEDIFF ( SELECTEDVALUE ( TableName[Date/Time] ), NextRow, SECOND )
    )