Saw this question a few more times but can't seem to get it fixed in my VBA code.
I need to calculate the total number of weeks in a given year comform ISO 8601.
When I use the datediff function: iNumWeeks = DateDiff("ww", "1/1/2015", "31/12/2015", vbMonday, vbFirstJan1)
it returns 52 while there are 53 weeks in 2015 (ISO 8601)
How can I get this done?
To quote from https://en.wikipedia.org/wiki/ISO_8601#Week_dates
28 December is always in the last week of its year.
Which means it's really as simple as
Public Function WeeksInYear(lYear As Long) As Long
WeeksInYear = DatePart("ww", DateSerial(lYear, 12, 28), vbMonday, vbFirstFourDays)
End Function