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akhaliq7
Post Prodigy
Post Prodigy

datediff months returning incorrect values

I am trying to get the duration between two dates in months and I am getting some inconsistent results

 

e.g.

 

start dateend dateduration in months
14 June 202205 July 20221
21 October 202312 January 20243
   

 

The above two durations are incorrect as whole months have not been taken into account.

 

Dax
Duration = DATEDIFF(start_date, end_date, MONTH)

 

1 ACCEPTED SOLUTION
Anonymous
Not applicable

Hi @akhaliq7 ,

Regarding your question, 'DATEDIFF' calculates the difference between two date months. Even if 'EndDate' is the first day of the new month, it counts as an additional month. You can modify your expression.

Column = 
VAR _a = DATEDIFF([start date],[end date],MONTH) 
VAR _b = IF(DAY([end date]) >= DAY([start date]) , _a ,_a - 1)
RETURN _b

vzhouwenmsft_0-1716946869182.png

If my understanding is wrong, please state your expected outcome.


Best Regards,
Wenbin Zhou
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

View solution in original post

2 REPLIES 2
Anonymous
Not applicable

Hi @akhaliq7 ,

Regarding your question, 'DATEDIFF' calculates the difference between two date months. Even if 'EndDate' is the first day of the new month, it counts as an additional month. You can modify your expression.

Column = 
VAR _a = DATEDIFF([start date],[end date],MONTH) 
VAR _b = IF(DAY([end date]) >= DAY([start date]) , _a ,_a - 1)
RETURN _b

vzhouwenmsft_0-1716946869182.png

If my understanding is wrong, please state your expected outcome.


Best Regards,
Wenbin Zhou
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

thanks @Anonymous 

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