Length Output to Excel

After querying gravity mains, I use CreateList<Graphic> , InsertIntoList<Graphic> and feed that into the Lengths Task.

But if I select more than one gravity main, the values of the length task are summed together. What I'm looking for is the 

ability to take each length result(s) and dump to either a text file and/or excel file, along with the AssetID of the gravity main.

How can this be achieved?

Walter