topic Re: Subtract previous average from current average in DAX Commands and Tips

Subtract previous average from current average

Anonymous — Tue, 26 Apr 2022 20:24:38 GMT

Hi Dax community,

I would like to calculate the difference in average satisfaction between the current and previous period but I could not figure out a DAX. I tried indexing and using the earlier function to no avail. I kept getting an error message with the earlier function. Is there a workaround?

Example Data

Survey Period	ID	Satisfaction
Jan-20	1	4
Jan-20	2	4
Jan-20	3	3
Jan-20	4	4
Jan-20	5	2
Jul-20	1	3
Jul-20	2	3
Jul-20	3	1
Jul-20	4	1
Jan-21	1	2
Jan-21	2	1
Jan-21	3	2
Jul-21	1	4
Jul-21	2	3
Jul-21	3	5
Jul-21	4	3
Jan-22	1	1
Jan-22	2	5
Jan-22	3	5
Jan-22	4	4
Jan-22	5	2

Result

Survey Period	Current	Previous	Difference
Jan-20	3.4	null	null
Jul-20	3.5	3.4	0.1
Jan-21	3	3.5	-0.5
Jul-21	3.25	3	0.25
Jan-22	4	3.25	0.75

Re: Subtract previous average from current average

amitchandak — Wed, 27 Apr 2022 01:27:07 GMT

Anonymous , Create a new tbale with distinct Survey and period and then try meausre like these

This Period = CALCULATE(sum('Table'[Qty]), FILTER(ALL(Period),Period[Period]=max(Period[Period]) && period[Survey] =max(period[Survey] ) ))
Last Period = CALCULATE(sum('Table'[Qty]), FILTER(ALL(Period),Period[Period]=max(Period[Period])-1 && period[Survey] =max(period[Survey] ) ))

period table = summarize(Table, Table[Survey], Table[Period])

Re: Subtract previous average from current average

v-cazheng-msft — Tue, 03 May 2022 05:12:35 GMT

Hi Anonymous,

You may try this solution.

1 Create a Calculated column

Date = VAR Month_ = SWITCH ( LEFT ( 'Table'[Survey Period], 3 ), "Jan", 1, "Feb", 2, "Mar", 3, "Apr", 4, "May", 5, "Jun", 6, "Jul", 7, "Aug", 8, "Sep", 9, "Oct", 10, "Nov", 11, "Dec", 12 ) VAR Year_ = 2000 + RIGHT ( 'Table'[Survey Period], 2 ) RETURN DATE ( Year_, Month_, 1 )

2 Create the following Measures

Current = CALCULATE(AVERAGE('Table'[Satisfaction]),FILTER(ALL('Table'),'Table'[Date]<=MAX('Table'[Date])))

Previous = CALCULATE([Current],FILTER(ALL('Table'),'Table'[Date]<MAX('Table'[Date])))

Difference = IF(ISBLANK([Previous]),BLANK(),[Current]-[Previous])

Then, the result looks like this.

Also, attach the pbix file as reference. Hope it helps.

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly. If I misunderstand your needs or you still have problems on it, please feel free to let me know. Thanks a lot!

Best Regards,

Community Support Team _ Caiyun