ISO dates yyww?

ISO dates yyww
SetAttr META "tags:{date|yyww}" is returning 1901 should be 2001 as this is week 1 of 2020

yy is the normal year code. YY is what you want if you're after the ISO year.!Documents/Codes_for_date_and_time.htm

Have been using yy for a long time
After looking at the manual I can see I had it wrong
What seems strange is that ISO Year is Y, YY or YYYY but ISO Week is w or ww that might be why I had it wrong, and for the last couple of years yyww was correct
Leo Jon
Happy New year for 2020