@saab,
Just read about the article in Swedish in Dagens Nzheter.
It is much longer, much more differentiated.
Included are everybody in a working age - no matter if they work or not
Amongst other things this article points out that just because you are at your work does not mean you work. Germany is on the lower part with 20,2 hours,
the Italians with 18 and the Swedes with 21,9.
This article also points out that it is not a cultural difference.
I would put a ? behind that.