=FPERIOD( )
Returns the current fiscal period.
Example:
If fiscal period 9 is the current period, this function:
=FPERIOD( )
would return a value of ?9".
BTW, you can insert this formula in a cell by using the Right Button | Insert Formula | Fiscal Information | Fiscal Period Number
I believe www.greatstatements.com has an example using FPERIOD() that is somewhat like what you want to do, although more complicated.
see: http://www.greatstatements.com/statements/landscapelegal/index.php