Hi, I am trying to find a formula how 2 calculate the sum between 2 Dates

I have a sheet contains a lot of information
Starting Date Qty Value
14/04/2009 10 1000
14/04/2009 15 2000
15/04/2009 2 1000
30/04/2009 1 1000

the sheet is long, & I need to create a summary report which shows the sum
by selecting the range according to the date

I have used the sumif but it doesn't work

please assist

thank you
--
LF