Need help on how to monitor sales per team/person

I am currently managing a group of 30 sales personnel that has been divided into groups of three sales men resulting in ten groups. I am interested in monitoring the sales record of one particular item in a given month such that I can get a total sum of sales that each team was able to conclude.
Getting the total from each salesman in the team and arranging it in order is not a problem at all. But doing the same for each teams is giving me a headache. I want to have the total sum of each sale per team which is the sum of all sales of each person in that team.
Does anyone have an idea how to solve this?
