I grew up being told that a cord was a stack 4'x4'x8', or 128cu.ft. Since I got my OWB, and all the research and reading I have done, I found that an actual "cord" of wood is 80 cu.ft. of solid wood, NO AIR spaces. That would be like if you were able to somehow melt it down into a solid mass, I guess. Anyway, I figure my cords at 100 cu.ft cut, split and stacked. I feel I am pretty particular about how I stack and I try to get it pretty tight. I burn approx 35 to 40 cord a year (based on this calculation). It's 5 pulp truck loads which they like to call 8 cord anyway, so I figure it's got to be close. 100 cu.ft. method, if nothing else, makes for easy calculation and quick reference.