cant figure out...my data is as follows
there are 3 columns, product,quarter and sale
there are 25 type of products
for each product quarter are made up from 2000 to 2010 (for each quarter value is given as Q12000,Q22000, Q32000,Q42000,Q12001...till Q42010)
sale quantity for each of the above in units is given
What is required is a formula to show separately 4 consecutive previous quarter sales for a chosen product..let us say for product K required sales figure is for Q22005, Q12005, Q42004, Q32004. What will be the best way to calculate? if a different quarter is selected will hte formula work?
regards
shabeer