Column A: Dates
Example
A1=8/23/2009
A2=9/5/2009
A3=7/29/2009
A4=8/21/2009

Column B: Names
Example
B1=John
B2=John
B3=Jane
B4=John

Column C: Amounts.
C1=$23.52
C2=$14.85
C3=$54.78
C4=$9.84


How can I put this information into a chart and group the amounts into
months. For example, August for John would sum: $$33.36, but for Jane would
sum $0.00