how to calculate sum between two months?

Dear all,
how can we calculate the sum in between two different months, like sum from jan to july.
to make my question clear I've uploaded sample workbook, please check.

regards,

Try this:

=SUMPRODUCT(((SHEET_MONTH&SHEET_YEAR)-($H$1&$I$2)>=0)*((SHEET_MONTH&SHEET_YEAR)-($J$1&$I$2)<=0),SHEET_VALUE)

I3=sumproduct(($a$2:$a$19=i2)*(month(sheet_month&0)>=month(h1&0))*((month(sheet_month&0)<=month(j1&0)))*(sheet_value))