Thread: Sum

I hope someone out there can help me tonight. I'm doing a workbook in 2007. My first worksheet is basically a summary sheet. My other worksheets are different types of clients and the invoices that we've paid that have been charged to our cost center. Here's the problem...

Sheet 2 is a list of all of the contractors we work with. The spreadsheet lists invoice dates, amounts and companies. What I want Excel to do is to calculate how much we've spent for a particular company in a month and place it in the summary sheet. For example:

Column A Column B Column C
10/31/2010 $15,056.69 Company A
10/31/2010 $3,000.00 Company B
12/21/2010 $28,441.69 Company A
1/19/2011 $712.61 Company D
1/19/2011 $50,635.66 Company D
1/27/2011 $3750.00 Company C
1/31/2011 $13,755.00 Coppany A
2/15/2011 $108,400.00 Company B
3/15/2011 $48,755.00 Company A

The name of the sheet is "Consultants-Auditors"

I've entered the following formula into my summary sheet and it keeps kicking back to me:
=dsum('Consultants-Auditors'!,'Consultants-Auditors'!B1,('Consultants-Auditors'!A2:A27>=1/31/2011)*('Consultants-Auditors'!C2:C27="Company A"))

What am I doing wrong?

I'll try that and let you know what happens. Thanks.