Good morning Niek
Tks for your prompt reply. What is said below suits the Excel help :
=WEEKNUM(A1,2)

will return 2, as 2000-Jan-9 is the last day of the second week of 2000.
Since the 2 in the formula indicates that weeks begin on Monday, week 2 is
computed as Monday, 2000-Jan-3 through Sunday, 2000-Jan-9.

But it does not work for me. For getting a correct week number, I must use 1
instead of 2. For getting Week 42, I must write (french version)
=NO.SEMAINE(A1,1)

Tks again
José

"Niek Otten" wrote:

It depends on your definition of week number.

See

http://www.cpearson.com/excel/weeknum.htm

--
Kind regards,

Niek Otten
Microsoft MVP - Excel


"José" wrote in message ...
| Gentlemen
| The argument type in french NO.SEMAINE help says to use 1, if the week
| begins a sunday and 2, if it begins a monday.
| I am obliged to use the reverse here to obtain a correct week number. I have
| probably missed something.
|
| Regards
| José
|
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