Forum Discussion
Help with simple Division Measure producing incorrect result
lbendlin Ashish_Mathur
I have determined the issue is due to rounding and the number of decimal places. As you can see below, Ive taken two seperate table exports from the same Power BI table. In the first export I had the measures in PBI formatted to two decimal places. This results in slightly inccorrect results as you can see in column J (comparing the PBI measure in column H with the same Excel calculation in column I). In the second export I had the measures in PBI formatted to four decimal places and the results are correct (column J shows zero difference when comparing columns H & I).
The math is correct when using four decimal places. When displaying two decimal places, the values in column F & H are rounded, however the calculation in column H is done with four decimal places in columns F & G.Power BI takes into consideration the decimal places that are not visible so simply taking an export (which exports just what is visible in the visual) can result to a misleading calculation in Excel.
Your numbers are accurate, the expectations are wrong.
Please use DIVIDE for divisions, and use variables.
Try not to nest measures too much as each of them comes with an implicit CALCULATE.
You also were using the wrong date field and not marking the calendar as Date table.
Attached a cleaned up version.
I don't understand how the expectations are wrong. I took an export from the file you provided and you can see that the calculation in column I produces slightly different results from the Power BI measure result in column H. It's very close, but if a user were to do the calcuation, they will find a different result from the Power BI measure result.
You are calculating percentage differences of two percentages, not of regular values.