yogi_Count Instances Of Different Items Based On The Value In The Parameter Column

                                          Google Spreadsheet   Post  #1320
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   Aug, 7 2013
user  Absolute Zeo (http://productforums.google.com/forum/?zx=d940ii538yk8#!category-topic/docs/spreadsheets/_LWrxc5pplo)
How do you total numbers in column B ONLY if they match criteria in Column A?

I am trying to find a formula that will add numbers in Column B ONLY if they match criteria in Column A.

A sample would be:

Column A    Column B

AVAT          1

ML              1

ML              1

AVAT          1

AVAT          1

AVAT          1

ML =           2

AVAT =       4

Please let me know how I can achieve this, I have been struggling with it for awhile.. thank you!

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