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xzfujc Frequent Visitor
Posts: 6
Registered: ‎09-13-2018 # Calculated Table for Month over Month Changes

Hello,

I have an archive table that looks like the following:

 Gate Emp. ID Count Month Year IA a123 351 9 2018 IRA a123 220 9 2018 NEW a123 26 9 2018 PSA a123 108 9 2018 IRA b456 39 9 2018 NEW b456 151 9 2018 PSA b456 55 9 2018 IA a123 453 9 2018 IRA a123 125 10 2018 NEW a123 35 10 2018 PSA a123 99 10 2018 IA b456 20 10 2018 IRA b456 9 10 2018 NEW b456 109 10 2018 PSA b456 66 10 2018

I want to create a calculated table to show the Month over Month Change in the count of "Gates" from month 9 to 10 by Employee ID (Emp. ID).  So I want a table that will look like the following:

 Gate Emp. ID Month Over Month Change IA a123 102 IRA a123 -95 NEW a123 9 PSA a123 -9 IA b456 20 IRA b456 -30 NEW b456 -42 PSA b456 11

This would allow me to show how things are moving from one gate to another each month for each employee and through the entire department. How can I code this in DAX so that the count from the Maximum Month in the table subracts the count from the previous month for each gate and employee combination?

I would need code to take into consideration how employee b456 has no IA gate in month 9 but has a count of 20 in the IA gate by month 10. Also I would need the code to take into consideration if the month is 1 then to subtract the count from month 12 of the previous year.

Any advice would be appreciated!

Accepted Solutions
dedelman_clng New Contributor
Posts: 455
Registered: ‎08-25-2016 ## Re: Calculated Table for Month over Month Changes

Hi @xzfujc

The best way is to think of measures instead of tables/columns.  You can then calculate the number of gates for the given month, the number of gates for the previous month, and then the difference.

You will need a date column to key off of, but since you have Month and Year, that's easy enough to create.

```//Calculated Column
Dt = DATE(Year, Month, 1)

//Measures
Total Gates = CALCULATE(SUM(Count))

LM Total Gates = CALCULATE([Total Gates], PREVIOUSMONTH(Dt))

Variance = [Total Gates] - [LM Total Gates]```

This will allow you to create a table visual, and if you want to look at it by just Gate instead of by Gate and Emp ID, the calculation will take care of itself.

Hope this helps

David

All Replies
dedelman_clng New Contributor
Posts: 455
Registered: ‎08-25-2016 ## Re: Calculated Table for Month over Month Changes

Hi @xzfujc

The best way is to think of measures instead of tables/columns.  You can then calculate the number of gates for the given month, the number of gates for the previous month, and then the difference.

You will need a date column to key off of, but since you have Month and Year, that's easy enough to create.

```//Calculated Column
Dt = DATE(Year, Month, 1)

//Measures
Total Gates = CALCULATE(SUM(Count))

LM Total Gates = CALCULATE([Total Gates], PREVIOUSMONTH(Dt))

Variance = [Total Gates] - [LM Total Gates]```

This will allow you to create a table visual, and if you want to look at it by just Gate instead of by Gate and Emp ID, the calculation will take care of itself.

Hope this helps

David

xzfujc Frequent Visitor
Posts: 6
Registered: ‎09-13-2018

## Re: Calculated Table for Month over Month Changes

I think your solution will accomplish what I need.

I am running into an issue with

`LM Total Gates = CALCULATE([Total Gates], PREVIOUSMONTH(Dt))`

It returns a 0. So my total variance is now equal to my total gates. Working on resolving. Is there a way to say something like the following?

`Total Gates = CALCULATE(SUM(Count), CurrentMonth(Dt))`

dedelman_clng New Contributor
Posts: 455
Registered: ‎08-25-2016

## Re: Calculated Table for Month over Month Changes

Change the variance calculation to

`Variance = IF(ISBLANK([LM Total Gates]), 0, [Total Gates] - [LM Total Gates])`

(or use BLANK() instead of 0 if you want to show no value in Variance for the first month) Hope this helps

David

xzfujc Frequent Visitor
Posts: 6
Registered: ‎09-13-2018

## Re: Calculated Table for Month over Month Changes

[ Edited ]

Really appreciate all the help, and I do believe the solution you provided is the solution I need. I am having trouble fully implementing it though, for some reason I can not get the LM Gates Total to sum anything which gives me a variance of 0.     Is there any reason you could think of why the the LM Total Gates returns null? Community Support Team
Posts: 1,591
Registered: ‎07-25-2018

## Re: Calculated Table for Month over Month Changes

Hi @xzfujc

You may drag the 'Dt' column to the table visual instead of 'Month' column.

`LM Total Gates = CALCULATE([Total Gates], PREVIOUSMONTH(Dt))`

Regards,

Cherie

Community Support Team _ Cherie Chen
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.
dedelman_clng New Contributor
Posts: 455
Registered: ‎08-25-2016

## Re: Calculated Table for Month over Month Changes

Also, you should have a dedicated CALENDAR table that has a relationship to Dt on your data table in order to fully utilize time intelligence like PREVIOUSMONTH()

Highlighted
xzfujc Frequent Visitor
Posts: 6
Registered: ‎09-13-2018

## Re: Calculated Table for Month over Month Changes

[ Edited ]

I can't explain it, but adding the .[Date] to the Dt field solved my problem. After adding the .[Date], the LM value was calculated correctly.

LM Total Gates = CALCULATE([Total Gates], PREVIOUSMONTH('Gates Count Archive'[Dt].[Date]))

Thanks for all your help!