NonStandard Month as Crosstab Columns - CR8.5

Question

I have a crosstab report that currently shows items (rows) by customer (columns).
They now wish to use that report to show columns as months.  This is easy enough with regular calendar months.  However their months are non-standard calendar months, for example.
November-2010 = 29th October to 28th November
December-2010 = 29th November to 26th December
January-2011 = 27th December to 30th January
etc.
Does anyone know how I can set up a formula to allow the grouping of the order dates on these types of date ranges?
I have tried working with a select case statement as in the below example (mostly hardcoded and not really dynamic right now) but it gives the error
"A Cross-Tab column has been specified on a non-recurring field."
As far as I can tell, with all the orders in the system, these columns have recurring data.
Local NumberVar nYear := 2010
Select {Orders.OrderDate}
    Case Date (nYear, 10, 29) to Date (nYear, 11, 28) :
        sColName := "November-10"
    Case Date (nYear, 11, 29) to Date (nYear, 12, 26) :
        sColName := "December-10"
    Default :
        sColName := "Other";
sColName ;
Anyone with any ideas at all?  Greatly appreciated.  rasinc

Answer 1

Thanks.  I went back to basics and did get this working after I got the If statement to work as you suggested.  But I hardcoded everything first, then added the variables back in.
Note the issue was the Shared NumberVar nYear := 2010 line.  With local variables, it seems to work.  Can't use a shared variable in this setup.  I have some more work to do but at least I know why it wasn't working.  Thanks.
Local StringVar sColName;
Local NumberVar nYear := 2010;
Select {Orders.OrderDate}
    Case Date (nYear, 10, 29) to Date (nYear, 11, 28) :
        sColName := "November-10"
    Case Date (nYear, 11, 29) to Date (nYear, 12, 26) :
        sColName := "December-10"
    Default :
        sColName := "Other";
sColName ;