Help please. I have a series of events listed by the date which they occur and I would like to write a SUMIF, which will return the sum for a given month. The data series is listed as follows:

17-Aug-09 $560,000.00
28-Aug-09 $266,400.00
04-Sep-09 $335,093.00
01-Sep-09 $225,000.00
08-Sep-09 $114,750.00
26-Aug-09 $260,000.00
28-Aug-09 $588,650.00
28-Sep-09 $129,000.00
17-Sep-09 $378,473.00
15-Sep-09 $360,000.00

September =
August =