You mean ISO week number

=INT((B4-DATE(YEAR(B4-WEEKDAY(B4-1)+4),1,3)+WEEKDAY(DATE(YEAR(B4-WEEKDAY(B4-
1)+4),1,3))+5)/7)

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HTH

Bob Phillips

"madhatter_scfc"
<madhatter_scfc.1vobic_1127246705.9655@excelforu m-nospam.com wrote in
message news:madhatter_scfc.1vobic_1127246705.9655@excelfo rum-nospam.com...

I've been creating a spreadsheet that takes figures from specific dates
and summarises into weeks and came accross this problem..
E.g.

=WEEKNUM("20/9/2005")
returns '39'.. it is however week 38!

However, using dates from last year e.g.
=weeknum("14/10/2004")
it returns the correct week 42.

Is it me or is this a bug?... i've tried looking for some sort of patch
but no joy!


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madhatter_scfc
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