Crystal Reports single value from a date range

Message

     I am very new to this sort of thing and not sure if this is simple, difficult, or even possible but I've been scanning for information for two days straight and haven't been able to get what I want.

I have a table where i want to report one quantity sum for a range of dates per item number.

For example this is what I have
Item                    Quantity             Date
1                          5                        Jan 1
1                          10                      Feb 5
1                          12                      Feb 10
2                          20                      Feb 8
2                          25                      Mar 6

I want to be able to input a date range say Feb 2 to Mar 1 and get these results
Item                    "new field"
1                          22
2                          20

Any help would be very appreciated, thank you. 

If it matters at all this information is being pulled from tables in Great Plains.