Grouping values by Months in different order

Hi Excel Guru
I have Excel files which I call the INPUT Files where Users will enter their respective data by Month. This file contains a list of unique Events’ Group_Codes and the values of how many Reds, Ambers, Greens for each of the tests conducted. Appropriate months will remain fixed i.e. from October 2012 to end of 2015.
In the second file I am trying to sum up the latest month’s values of Reds, Ambers and Greens for each of the category, by Month and the months are running backwards e.g. if March’2013 (columns – N to P) is the current month then Ferbruary’2013 = Z,AA AB, January’2013 = AC,AD & AE, December’2012 = AF,AG & AH and so on (until March’2012 = BG, BH & BI).

On another project I only had one set of criteria so I used the following formula and it worked fine but in this case I have an additional criteria i.e. Months to consider i.e. if the Month name changes from March’2013 to January’2013 OR April’2013 then I would like the formula to group the values and display in correctly in appropriately.
=SUMPRODUCT(--([DS_TEST2.xlsm]RAGs_Summary!$C$5:$C$21=G24),--([DS_TEST2.xlsm]RAGs_Summary!$I$5:$I$21))

I am attaching two sample files.

Thanking you in advance.
Dhiresh