yogi_Compute Sum Of Expenses By Specified Month Year And SheetName

                                          Google Spreadsheet   Post  #1427
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   Nov 23, 2013
question by rkhubb (https://productforums.google.com/forum/#!mydiscussions/docs/TqiI2OvZyHA)
Using a cell to reference a sheet name in a Sumif formula
Hello, 

...And thanks in advance for your help...

I am creating an accounting spreadsheet that i would like to accommodate ease of adding account to the doc to the summary page.  The doc will work as follows:

In the Summary tab the account template column will be copied when a new account is being added,  change the year row if needed (B6 in this example) and then type the name in the account name cell (C3 here) that references a tab name copied from and renamed from an account tab template.  

The cell I need help with is C7 (in "summary" tab), which will sum all expenses for the month of january.  The problem i am having is getting the formula to accept the sheet name when trying to reference cell C3.

I looked this up... thought i found a solution, but anything i tried returns an error.  The closest I've come is the following that returns an error "Argument must be a range":

=(sumif(""&C2&"!B:B","<2-1-&B6&",""&C2&"!E:E"))-(sumif(""&C2&"!B:B","<1-1-&B6&",""&C2&"!E:E"))

Sheet: https://docs.google.com/spreadsheet/ccc?key=0AlJo4UnT5CF-dEhoLUVkTU5YRC1LNGx6MkhfZjlCY0E&usp=sharing

thanks again,

keith

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