Power Bi not calculating percentage correctly

[Anonymous]

Hello,
I'm running into a strange result when attemting to calculate percentage difference between 2 numbers and would really appreciate any incite into the problem. 

Measure: 

% Change =

     VAR diff =

       CALCULATE(TableA[Measure_Total_Sum] - TableA[Measure_Total_Sum_Prior_Yr])

     RETURN

       DIVIDE(diff , TableA[Measure_Total_Sum_Prior_Yr])

Using the actual numbers from my table, the calculation ends up being: (1,439,699 - 1,514,506) / 1,514,506 * 100 

Power BI ends up with -29.61%.

However, when I do this same calculation on a calculator, the end result is -4.94%. 

Now, here's the odd part... If I add the columns in a visual table, Power BI gets the same result as my calculator. 

[Anonymous · Accepted solution]

So, it turns out, I was able to resolve this by going in the direction of all the help on this thread. I not only applied the year as a filter on the page, but also applied the months as a filter on the page as well. By choosing not to include the month of Oct. which is not complete yet, the measure calculates the percentage correctly. Thank you all who contributed. 

[HoangHugo]

Hi, the calculation is right, may be error from TableA[Measure_Total_Sum_Prior_Yr]. Can you share detail DAX of measure, and time table you are using.

[Anonymous]

Thanks for your reply. 

There are 2 measures associated with this particular measure. They are:

Total Transactions = Sum(TableA[Transactions])

Total Transactions Prior Yr = 
  CALCULATE(TableA[Total Transactions], PARALLELPERIOD('Calendar'[Date],-12,MONTH))

The Calendar Table is a standard Calendar table I use with all reports. 

When I add the months to the visual table (mentioned above), the row totals are all correct. 

Here's a screenshot of the actual report: 

[Ashish_Mathur]

Hi,

From the Calendar Table, drag the Year field in a slicer and select 2022.

[Anonymous]

Thank you for your reply, but I did not mention, I already had a filter on the page for 2022. Never the less, I also added a slicer and still received the same results. 

[HoangHugo]

Hi, I understand you want to calculate YOY%, so need to calculate result of current Year to Date, try this one

Measure result of YTD = CALCULATE([Total Transaction], DATEYTD('Calendar'[Date]))

Measure result of Prior Year =CALCULATE(TableA[Total Transactions], PARALLELPERIOD('Calendar'[Date],-12,MONTH))

then, use your orginal formula to calculate %difference 

[Anonymous]

Thank you, but as you can see above, I am already utilizing a date slicer and originally had used a date filter on the page. So, the total already reflected YTD.