Here is the situation.

1)Say , I have a table fiscal_accrual
    Create or replace table fiscal_accrual
   (fiscal_accrual_id        pls_integer,
    Amount                      NUMBER,
    fiscal_month              DATE ) e.g like the first date of each month
    );
2) I will want a procedure to return the average   amount for 4 months based on particular month based on a month passed as a parameter.
Cursors may be used .
    
   Calculation is done as per below: (July and August can never be a part of the resultset for calculation
    a) If the passed parameter month is Feb,
                   then calculate the average by taking amount from 3 prior months and 1 succeeding month. e.i amount of Nov,Dec,Jan & March
    b)if the passed parameter month is March,
                 then calculate   the average by taking bonus_amt from 4 prior months e.i   amount of   Nov,Dec,Jan ,Feb
    c)if the passed parameter month is April,
                 then calculate   the average by taking amount from 4 successive months e.i bonus amt of   may,Jun,Sept ,Oct
    d)if the passed parameter month is May,
                 then calculate   the average by taking amount from 1 prior month and 3 successive months e.i bonus amt of   April,Jun,Sept ,Oct
     e)if the passed parameter month is June,
                 then calculate   the average by taking amount from 2 prior month and   2 successive months e.i bonus amt of   April,May,Sep ,Oct
    f)if the passed parameter month is July,
                 then calculate   the average by taking amount from 2 prior month and
And likewise, but never include july and august .

   d) basically taking average of 4 months based on above conditions.If no rows are returned, just get 4 months in any order.

    No hard coding is allowed. Should be dynamic