yogi_Compute For Each Month Of Dates in ColumnA (Sum of AmountB) - (Sum Of AmountC)

                                          Google Spreadsheet   Post  #1258
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   Jun 22, 2013
user Jarorosor (http://productforums.google.com/forum/#!category-topic/docs/spreadsheets/zV2UVY_ZHhY)
How to sum between to specific dates 
Hi!

I´m trying to calculate values from two columns within each month.

For example

A                         B               C          Months

--------------------------------------------------------------------

2013-06-01          150                          June: 240

2013-06-05          275                          July: 45

2013-06-27                          185          August: -10

2013-07-01                          75

2013-07-20         120

2013-08-01         50

2013-08-18                         25

2013-08-25                         35

So what i'm trying to do is sum column B minus column C for each month with a formula and I can't get it right using SUMif.

Anyone who can help?

Thanks in advance.

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