Year of the week : How to ?

How to retrieve the year based on week of a date ?

If I use datepart('year', aDate), I get the year of the date.
If I use datepart('week', aDate), I get the week of the date.
But these aren't corelated. So when aDate is Dec 31st 2001, I get 2001, and
the week is 1. I'd like to have 2002 for the year in this case.

Is there a simple way to do this ?

Emmanuel Guyot
8 Rue des Montes
45100 Orlans
Web site : http://www.increg.com