Ceiling ( Position ( "JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC" ; Left ( Upper ( MonthName ) ; 3 ) ; 1 ; 1 ) / 3 )
raybaudi is right,
just wanan say that if ur gonna use that expression a lot u could go to "File --> Manage --> Custom Functions " and add it to filemaker functions database and use it like any other predefined function, may be u 'll need it in the future .
Thanks to you both. Would never have worked this formula out, so you have saved me lots of time. And I now have a custom function....