Correct Year+Week Number for Jan 1st

I'm trying to sort files in folders named YYYY-WW, where YYYY is the Year and WW is the Week Number. I'm interested in following the ISO 8601 scheme, so Jan 1st 2017 will be in 2016W52, but when Hazel sorts that week it creates a folder named 2017-52 for it.
Is there a way of generating the correct folder name which would be 2016-52?

You can try setting your system calendar to ISO 8601. Not sure how that affects other aspects of your system but Hazel uses that calendar for this type of thing.