How Much Thread Do I Need?

I was asking myself this question now that I'll be getting started on quilting, as opposed to piecing the tops, for the Jan and Feb UFO Challenge quilts. My 'Dragonfly' quilt measures 72"x93", so I guess that falls into the double bed quilt size. I have a 2,000 yd spool of Superior's King Tut quilting thread, variegated, which I plan to use and was wondering if that would be enough. I Googled my question, and voila, Superior (link here) actually has a small chart showing how much is needed and explains some of the variables giving correlating thread amounts. So, even if I were to heavily quilt this project (that's not planned), I should be safe, even if I use the same thread in the bobbin. O' happy day! :)