Ah ha....that is exactly the comment I have been searching for. Thank you.
There can't be that many yards of fabric in a hammock...I assume that is what the weight of the fabric is measuring (2.5 oz per yard and 1.9 oz per yard).
Just to clarify, it's the square yard not the linear yard. So, say your hammock is 10' long by 5' wide gives 50 sq ft/ 9 sq ft in a sq yd = 5.56 sq yd x 1.9 oz/yd = 10.56 oz total weight of the fabric.