Need a sum formual with 2 critera and count

I am looking for a sum formual that will sum Month To Date data for current year prior year. I am currently working with sumifs because I need two sum criteria, the Year and Month. Issue that I am having is currently I have 4 weeks of September data for 2014 so I would only want to sum the same 4 weeks of September data from 2013. A straight sumifs for 2013 will not work because I would pick up the 5th Sept week from 2013 that currently has not happended in 2014 so I would be comparing 5 weeks to 4. I know I can accomplish what I need with offset() formulas but I am trying to stay away from them. Any suggestions? Example attached.


Thank you,