topic Re: Bug Report: DATESINPERIOD Function – Leap Year Handling in DAX Commands and Tips

Bug Report: DATESINPERIOD Function – Leap Year Handling

Mattiar — Thu, 20 Mar 2025 13:34:59 GMT

I’d like to report a bug in the DATESINPERIOD function:

DATESINPERIOD (
'Data'[data],
SELECTEDVALUE ( 'Data'[data] ),
-1,
YEAR
)

When I select the exact date of February 28, 2025, it should go back to February 29, 2024, as stated in the documentation, but it doesn’t handle the leap year day properly.

This could lead to misunderstandings in reports.

Mattia

Re: Bug Report: DATESINPERIOD Function – Leap Year Handling

Greg_Deckler — Thu, 20 Mar 2025 14:00:43 GMT

Mattiar Yeah, in general, stay away from the DAX TI functions IMHO. You may find this helpful - https://community.powerbi.com/t5/Community-Blog/To-bleep-With-Time-Intelligence/ba-p/1260000

Also, see if my Time Intelligence the Hard Way provides a different way of accomplishing what you are going for.

https://community.powerbi.com/t5/Quick-Measures-Gallery/Time-Intelligence-quot-The-Hard-Way-quot-TITHW/m-p/434008

Re: Bug Report: DATESINPERIOD Function – Leap Year Handling

Mattiar — Thu, 20 Mar 2025 14:05:22 GMT

Thanks, Greg,
your links are always relevant.
"Unfortunately," I share your opinion about the TI functions, but at the same time, I hope they will be improved and cleaned of their bugs over time.

Re: Bug Report: DATESINPERIOD Function – Leap Year Handling

Mattiar — Thu, 20 Mar 2025 15:53:43 GMT

A workaround was to propose a month-year selector instead of the date field. This way, you don’t have any issues. I’m reporting the measure for completeness.

var _ultimodelmese =

CALCULATE(

MAX('Data'[data]),

ALLEXCEPT('Data', 'Data'[anno], 'Data'[mese_anno])

)

RETURN

CALCULATE(

[Amount],

DATESINPERIOD(

'Data'[data],

_ultimodelmese,

-1,

YEAR

)