Calculate week number when week starts on Sunday

Hello,

I'm using below to calculate the week number from a date in a SharePoint list. Now I want to start the week on Sunday instead of Monday. What do I need to change for this?

Can anyone help me?

=CONCATENATE(TEXT(IF(INT((Productiedatum-DATE(YEAR(Productiedatum);1;1)+(TEXT(WEEKDAY(DATE(YEAR(Productiedatum);1;1)-1);"d")))/7)=0;52;INT((Productiedatum-DATE(YEAR(Productiedatum);1;1)+(TEXT(WEEKDAY(DATE(YEAR(Productiedatum);1;1)-1);"d")))/7));"0"))

Kind regards,

Hans