Dashboard excel monthwise sum

HI,

Data is coming dad wise ,i have calculate monthwise,find the below example

date               Amount

01/04/2014     56

02/04/2014     45

03/06/2014     30

04/06/2014     10

i nedd like this each month wise sum

04.2014     101

06.2014     40

find the screen shot,Actually data will Dynamically,according to that inform the sumif functionh

how to do ,guide me