Query regarding aggregation

Hello, I have a query regarding Bex.

I have a dso which has customer data in it with multiple dates like this:

Customer      ZDTE            Quantity
101                01/01/2014        10
101                02/01/2014        25
101                02/28/2014        45
102                01/01/2013        19
102                02/02/2014        20

My requirement is to get the latest date with aggregated quantity: like this

Customer      ZDTE            Quantity
101                 02/28/2014       80
102                 02/02/2014       39

Do you know how to do this at Bex level?

Thanks.