Auto Add repeated items

Hi, Help needed,
I have a document with 2500 rows of data. It is basically Name, amount sold, % etc.
I have data sorted these by name and I have many duplicates as my team work in different locations. I am hoping there is a way to total the amount sold for each duplicate name, without having to add a row and auto sum each time. Then I can simply data sort by amount sold to see my best performers. Any tips help and advice greatly appreciated
Cheers Ped

Re: Auto Add repeated items

Thanks Junho, looks a great site for what i need , Also I will attach an Example of what I am looking at could you point out where and how I would add the subtotals. I am trying to avoid adding rows then doing an auto sum as I have 2500 rows to go through and most have multiple entries

Re: Auto Add repeated items

Thanks , Exactly what I am after , one more thing when I try it I have lots of drop down lists not a data list and then all the relevenat headings aloong the top. I ahve also notoced that mine appear as "count" not "sum". Any ideas ?