Week number not matching date

[AnnaML]

Hello, 

I have an issue with week numbers. I have created a column called YearWeek using the following: 

YearWeek = IF(WEEKNUM([Date].[Date])<10,FORMAT([Date],"YY0WW"),FORMAT([Date],"YYWW"))

I put date and yearweek into a table and got the following:

My issues is that the weeks does not match the right dates. For example in this table it shows that week 3 is between 10-16 of January but in reality it's between 17-24 January. I want week 1 to start with January 3rd. 

Can someone please help me? 

Thankful for support, 

[Anonymous]

Hello, how about if I want the week number only, WW?

Thank you.

[themistoklis]

@AnnaML 

If you want to use a Iso YEAR Week the formula should be like this:

YearWeek = IF(WEEKNUM('Calendar'[Date], 21)=53 && MONTH('Calendar'[Date])=1, YEAR('Calendar'[Date]) -1, YEAR('Calendar'[Date])) & "-" & WEEKNUM('Calendar'[Date], 21)

You need to put another parameter in weeknum function.... the parameter with value 21.

See also link below:

https://community.powerbi.com/t5/Desktop/Looking-for-real-year-week/m-p/1591530#M646306

[AnnaML]

Hello, 

Thanks for your answere. It seems to work. Although is it possible to show YYWW instead of YYYY-WW? 

Kind Regards

[themistoklis · Accepted solution]

@AnnaML 

Try this formula:

YearWeek = RIGHT(IF(WEEKNUM('Calendar'[Date], 21)=53 && MONTH('Calendar'[Date])=1, YEAR('Calendar'[Date]) -1, YEAR('Calendar'[Date])),2) & WEEKNUM('Calendar'[Date], 21)

[AnnaML]

Thanks for the support, it really helped!