<y I know which is the correct Week Number

That depends on your definition of Week Number.

To learn all about week numbers and Excel, read this:

http://msdn.microsoft.com/en-us/library/bb277364.aspx

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Kind regards,

Niek Otten
Microsoft MVP - Excel

"exalan" wrote in message
...
Hi,

When I use the weeknum formula to calculate the week number on today's
date
(5th April 2010), the result is 15 (week no.15) irrespective of the return
type 1 or 2. However, according to the Calendar in my Lotus Notes, the
week
starting 5th April 2010 is Week no.14.

I think the difference in Week No. between the two is due to cumulative
effect of Week no.1 in Lotus Notes starts from 4th January 2010 whereas
Excel's Weeknum starts Week no.1 from 1st January 2010.

May I know which is the correct Week Number for 5th April 2010, Week no.14
or Week no.15?

Many thanks...
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exalan