yogi_Compute Row By Row Amount For Category From Entries In Check Register

                                         Google Spreadsheet   Post  #1626
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   May-08-2014
post by: Check Register (https://productforums.google.com/forum/#!category-topic/docs/spreadsheets/7zzBa5XyvyY)
Summing Drop Down Categories

In the link below, I would like to have the various categories in Column G, to be Summed in Column B using an "iferror" function. I am new to this function and would like any help on how to build this function and/or better understanding of how it works. 

Thanks for any help

https://docs.google.com/spreadsheets/d/1MUPyym3n_CNXPAem6K7xGX7SfyMWsrzv6BNIMojH3RE/edit?usp=sharing

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