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drivas771994's avatar
drivas771994
Icon for Helper II rankHelper II
8 years ago
Solved

Is there a formula for calculating the difference between rows.

Hi,

 

I'm trying to calculate the difference between two values in the same column. For example, I have a student (John Doe) who took one test on 9/1/2018 and received a 76 and then retook the test on 9/5/2018 and got an 88. I want to make a calculated column for the difference in the scores. Is this possible? And would it be specific to each individual student?

Need Help

7 Replies

  • Zubair_Muhammad's avatar
    Zubair_Muhammad
    Icon for Community Champion rankCommunity Champion
    8 years ago

    drivas771994

     

    Try this pattern

     

    Difference from Previous Score =
VAR previousrow =
    TOPN (
        1,
        FILTER (
            Table1,
            [Student] = EARLIER ( [Student] )
                && [Test Date] < EARLIER ( [Test Date] )
        ),
        [Test Date], DESC
    )
VAR previousscore =
    MINX ( previousrow, [Score] )
RETURN
    IF ( NOT ( ISBLANK ( previousscore ) ), [Score] - previousscore )