Ahh... I see exactly what you mean now. So the text file, looks exactly like this?
Code:
Apple 10 in
Apple 5 out
Apple 3 in 
Shoes 90 in
Shoes 5 out
Pants 23 in
Pants 44 in
Pants 9 out
And for the listView display, you want, Apple, Shoes and Pants.

Apple = -5 + 3
Shoes = 90 + -5
Pants = 23 + 44 + -9

Why do you have 8 then for apple? Should that not be the sum of the 5 that went out (-5) + 3 in?