Save file with ISO correct Workweek

Hello Everyone,

Last year this portion of my macro worked great assigning the current work week according to ISO standards.

ActiveWorkbook.SaveAs Application.UserName & "_" & "FCST" & "_" & Format(Date, "MMDDYYYY") & "_" & "CW" & Format(Date, "WW", vbUseSystemDayOfWeek, vbUseSystem)

Since the change of the year it does not work. For instance, today I ran it and it says we are in work week 3, but ISO says we are in work week 2. I don't know how to fix and I can't seem to find the answer.

Thoughts?

Thanks,
Matt