=MONTH(DATE(YEAR(A1),MONTH(A1)-1,1))

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Kind Regards,

Niek Otten

Microsoft MVP - Excel


"Nigel" wrote in message
...
Hi All
What is the simplest way to determine from a DATE the prior month number?

eg Using European Date format
1/03/2005 would give 2 as the prior month
10/01/2005 would give 12


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Cheers
Nigel