monthly minimum in a yearly time series

[DELCLAUX Francois <francois.delclaux@xxxxxxxxxxxxxxxxxxx>]

Hi Ferret users,

I have a 45 year time series of monthly values .
I would like to get the monthly minimum for each year, ie 45 minimum values.
What is the best way to do this operation ?
Thanks in advance

--
Francois DELCLAUX 
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UMR HydroSciences Montpellier
Universite Montpellier II - Place Eugene Bataillon
Case courrier MSE
34095  Montpellier Cedex 5      FRANCE        
http://www.hydrosciences.org/   
mailto: delclaux@msem.univ-montp2.fr
Tel : (33) (0)4 67 14 90 11      Fax : (33) (0)4 67 14 47 74
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