How do I specify certain date as the first week and calculate the week number in dax

[Sfns_2024s]

How do I get the week number based on the date that I set as first week ? For example 2023-05-21 should be Week 1 instead of 2023-01-01

Thanks,

[v-jialongy-msft · Accepted solution]

Hi @Sfns_2024s 

Try the following dax

Custom Week Number = 
VAR CustomStartDate = DATE(2023, 5, 21)
VAR CurrentDate = 'Table'[Date]  .[Date]
VAR DaysDiff = CurrentDate - CustomStartDate
VAR WeeksFromCustomStart = INT(DaysDiff / 7)
RETURN IF(DaysDiff < 0, BLANK(), WeeksFromCustomStart + 1)

Best Regards,

Jayleny

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

[lbendlin]

Use an external reference table for your calendar where you have the fiscal year or fiscal quarter weeks marked as a dedicated column.  This can be an Excel file on a SharePoint, for example.