How Do i correctly calculate the sum of a column of percentages?

[CraigBlackman]

Hi All,

I have a simple table with rows which are days of the month. Two columns Sales for each day from 2015 and a second column for 2014. 

I want to calcuate the percentage change, which i can do on a row to row basis no problem.

The issue is that when that percentage column is sumed, it is incorrectly calulcating the total percentage cange, its adding each row together so i am getting very high results like 1423% increase when the actual is something like 10.45% for example.

I cannot figure out the correct DAX formula to correct this. Any help appreciated.

Thanks

Craig

[willz06jw]

I found that my problem was that when I created the object, I created it as a 'New Column' instead of a 'New Measure'.  

This caused it to add the percentages for each row (since there was a percentage created for each row, because it was a 'column' in the actual data).

[willz06jw]

I have the exact same problem.  Of course, the answer given above gives no help.  How did you resolve the issue?

[ashishrj · Accepted solution]

@CraigBlackman You can use different DAX (Data Analysis Expression) functions to achieve your result

[andre]

create a new measure

Pct = divide(sum(tableName[columnA]), sum(tableName[columnB]))